diff --git a/llvm/include/llvm/MC/StringTableBuilder.h b/llvm/include/llvm/MC/StringTableBuilder.h
--- a/llvm/include/llvm/MC/StringTableBuilder.h
+++ b/llvm/include/llvm/MC/StringTableBuilder.h
@@ -37,6 +37,7 @@
 private:
   DenseMap<CachedHashStringRef, size_t> StringIndexMap;
   size_t Size = 0;
+  size_t Length = 0;
   Kind K;
   unsigned Alignment;
   bool Finalized = false;
@@ -80,6 +81,7 @@
   }
 
   size_t getSize() const { return Size; }
+  void setLength(size_t L) { Length = L; };
   void clear();
 
   void write(raw_ostream &OS) const;
diff --git a/llvm/include/llvm/ObjectYAML/XCOFFYAML.h b/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
--- a/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
+++ b/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
@@ -59,10 +59,17 @@
   uint8_t NumberOfAuxEntries;
 };
 
+struct StringTable {
+  bool isSuppress;
+  uint32_t Length;
+  std::vector<StringRef> Strings;
+};
+
 struct Object {
   FileHeader Header;
   std::vector<Section> Sections;
   std::vector<Symbol> Symbols;
+  StringTable StrTbl;
   Object();
 };
 } // namespace XCOFFYAML
@@ -100,6 +107,10 @@
   static void mapping(IO &IO, XCOFFYAML::Section &Sec);
 };
 
+template <> struct MappingTraits<XCOFFYAML::StringTable> {
+  static void mapping(IO &IO, XCOFFYAML::StringTable &Str);
+};
+
 template <> struct MappingTraits<XCOFFYAML::Object> {
   static void mapping(IO &IO, XCOFFYAML::Object &Obj);
 };
diff --git a/llvm/lib/MC/StringTableBuilder.cpp b/llvm/lib/MC/StringTableBuilder.cpp
--- a/llvm/lib/MC/StringTableBuilder.cpp
+++ b/llvm/lib/MC/StringTableBuilder.cpp
@@ -77,9 +77,9 @@
   // The COFF formats store the size of the string table in the first 4 bytes.
   // For Windows, the format is little-endian; for AIX, it is big-endian.
   if (K == WinCOFF)
-    support::endian::write32le(Buf, Size);
+    support::endian::write32le(Buf, Length ? Length : Size);
   else if (K == XCOFF)
-    support::endian::write32be(Buf, Size);
+    support::endian::write32be(Buf, Length ? Length : Size);
 }
 
 // Returns the character at Pos from end of a string.
diff --git a/llvm/lib/ObjectYAML/XCOFFEmitter.cpp b/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
--- a/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
+++ b/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
@@ -33,8 +33,9 @@
 public:
   XCOFFWriter(XCOFFYAML::Object &Obj, raw_ostream &OS, yaml::ErrorHandler EH)
       : Obj(Obj), W(OS, support::big), ErrHandler(EH),
-        Strings(StringTableBuilder::XCOFF) {
+        StrTbl(StringTableBuilder::XCOFF) {
     Is64Bit = Obj.Header.Magic == (llvm::yaml::Hex16)XCOFF::XCOFF64;
+    isStrTblSuppress = Obj.StrTbl.isSuppress;
   }
   bool writeXCOFF();
 
@@ -43,6 +44,7 @@
   bool initFileHeader(uint64_t CurrentOffset);
   bool initSectionHeader(uint64_t &CurrentOffset);
   bool initRelocations(uint64_t &CurrentOffset);
+  void initStringTable();
   bool assignAddressesAndIndices();
   void writeFileHeader();
   void writeSectionHeader();
@@ -54,7 +56,8 @@
   bool Is64Bit = false;
   support::endian::Writer W;
   yaml::ErrorHandler ErrHandler;
-  StringTableBuilder Strings;
+  StringTableBuilder StrTbl;
+  bool isStrTblSuppress = false;
   uint64_t StartOffset;
   // Map the section name to its corrresponding section index.
   DenseMap<StringRef, int16_t> SectionIndexMap = {
@@ -140,20 +143,39 @@
   return initRelocations(CurrentOffset);
 }
 
+void XCOFFWriter::initStringTable() {
+  StrTbl.clear();
+  // Set the string table length field with the custom value.
+  if (Obj.StrTbl.Length)
+    StrTbl.setLength(Obj.StrTbl.Length);
+
+  for (const StringRef &StringEnt : Obj.StrTbl.Strings)
+    StrTbl.add(StringEnt);
+
+  size_t StrTblSize = Obj.StrTbl.Strings.size();
+  size_t StrTblIdx = 0;
+  for (XCOFFYAML::Symbol &YamlSym : Obj.Symbols) {
+    if (nameShouldBeInStringTable(YamlSym.SymbolName)) {
+      if (StrTblIdx < StrTblSize) {
+        // Overwrite the symbol name with the value in the string table.
+        YamlSym.SymbolName = Obj.StrTbl.Strings[StrTblIdx];
+        ++StrTblIdx;
+      } else
+        StrTbl.add(YamlSym.SymbolName);
+    }
+  }
+  StrTbl.finalize();
+}
+
 bool XCOFFWriter::initFileHeader(uint64_t CurrentOffset) {
   // The default format of the object file is XCOFF32.
   InitFileHdr.Magic = XCOFF::XCOFF32;
   InitFileHdr.NumberOfSections = Obj.Sections.size();
   InitFileHdr.NumberOfSymTableEntries = Obj.Symbols.size();
 
-  for (const XCOFFYAML::Symbol &YamlSym : Obj.Symbols) {
+  for (const XCOFFYAML::Symbol &YamlSym : Obj.Symbols)
     // Add the number of auxiliary symbols to the total number.
     InitFileHdr.NumberOfSymTableEntries += YamlSym.NumberOfAuxEntries;
-    if (nameShouldBeInStringTable(YamlSym.SymbolName))
-      Strings.add(YamlSym.SymbolName);
-  }
-  // Finalize the string table.
-  Strings.finalize();
 
   // Calculate SymbolTableOffset for the file header.
   if (InitFileHdr.NumberOfSymTableEntries) {
@@ -171,7 +193,6 @@
 }
 
 bool XCOFFWriter::assignAddressesAndIndices() {
-  Strings.clear();
   uint64_t FileHdrSize =
       Is64Bit ? XCOFF::FileHeaderSize64 : XCOFF::FileHeaderSize32;
   uint64_t SecHdrSize =
@@ -182,6 +203,10 @@
   // Calculate section header info.
   if (!initSectionHeader(CurrentOffset))
     return false;
+  
+  // Customize the string table.
+  initStringTable();
+
   // Calculate file header info.
   return initFileHeader(CurrentOffset);
 }
@@ -309,13 +334,13 @@
   for (const XCOFFYAML::Symbol &YamlSym : Obj.Symbols) {
     if (Is64Bit) {
       W.write<uint64_t>(YamlSym.Value);
-      W.write<uint32_t>(Strings.getOffset(YamlSym.SymbolName));
+      W.write<uint32_t>(StrTbl.getOffset(YamlSym.SymbolName));
     } else {
       if (nameShouldBeInStringTable(YamlSym.SymbolName)) {
         // For XCOFF32: A value of 0 indicates that the symbol name is in the
         // string table.
         W.write<int32_t>(0);
-        W.write<uint32_t>(Strings.getOffset(YamlSym.SymbolName));
+        W.write<uint32_t>(StrTbl.getOffset(YamlSym.SymbolName));
       } else {
         writeName(YamlSym.SymbolName, W);
       }
@@ -355,8 +380,8 @@
   if (!Obj.Symbols.empty() && !writeSymbols())
     return false;
   // Write the string table.
-  if (Strings.getSize() > 4)
-    Strings.write(W.OS);
+  if (StrTbl.getSize() > 4 && !isStrTblSuppress)
+    StrTbl.write(W.OS);
   return true;
 }
 
diff --git a/llvm/lib/ObjectYAML/XCOFFYAML.cpp b/llvm/lib/ObjectYAML/XCOFFYAML.cpp
--- a/llvm/lib/ObjectYAML/XCOFFYAML.cpp
+++ b/llvm/lib/ObjectYAML/XCOFFYAML.cpp
@@ -143,7 +143,7 @@
 }
 
 void MappingTraits<XCOFFYAML::Symbol>::mapping(IO &IO, XCOFFYAML::Symbol &S) {
-  IO.mapRequired("Name", S.SymbolName);
+  IO.mapOptional("Name", S.SymbolName);
   IO.mapOptional("Value", S.Value);
   IO.mapOptional("Section", S.SectionName);
   IO.mapOptional("Type", S.Type);
@@ -151,11 +151,18 @@
   IO.mapOptional("NumberOfAuxEntries", S.NumberOfAuxEntries);
 }
 
+void MappingTraits<XCOFFYAML::StringTable>::mapping(IO &IO, XCOFFYAML::StringTable &Str) {
+  IO.mapOptional("Suppress", Str.isSuppress);
+  IO.mapOptional("Length", Str.Length);
+  IO.mapOptional("Strings", Str.Strings);
+}
+
 void MappingTraits<XCOFFYAML::Object>::mapping(IO &IO, XCOFFYAML::Object &Obj) {
   IO.mapTag("!XCOFF", true);
   IO.mapRequired("FileHeader", Obj.Header);
   IO.mapOptional("Sections", Obj.Sections);
   IO.mapOptional("Symbols", Obj.Symbols);
+  IO.mapOptional("StringTable", Obj.StrTbl);
 }
 
 } // namespace yaml
diff --git a/llvm/test/tools/yaml2obj/XCOFF/string-table.yaml b/llvm/test/tools/yaml2obj/XCOFF/string-table.yaml
--- a/llvm/test/tools/yaml2obj/XCOFF/string-table.yaml
+++ b/llvm/test/tools/yaml2obj/XCOFF/string-table.yaml
@@ -0,0 +1,137 @@
+## Check that yaml2obj is able to customize the string table.
+
+## Case 1: a string table with implicit contents.
+# RUN: yaml2obj --docnum=1 %s -o %t1
+# RUN: llvm-readobj %t1 --string-table | FileCheck %s --check-prefix=CASE1
+
+# CASE1:      StringTable {
+# CASE1-NEXT:   Length (in bytes): 14
+# CASE1-NEXT:   [     4]   alongname
+# CASE1-NEXT: }
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x1DF
+Symbols:
+  - Name: alongname
+
+## Case 2: a custom string table with specific contents and length. 
+##         In this case symbol names in string table are overwritten 
+##         by specific values.
+# RUN: yaml2obj --docnum=2 %s -o %t2
+# RUN: llvm-readobj %t2 --symbols --string-table | FileCheck %s --check-prefix=CASE2
+
+# CASE2:      Symbols [
+# CASE2-NEXT:   Symbol {
+# CASE2-NEXT:     Index: 0
+# CASE2-NEXT:     Name: text
+# CASE2-NEXT:     Value: 0x0
+# CASE2-NEXT:     Section: N_UNDEF
+# CASE2-NEXT:     Type: 0x0
+# CASE2-NEXT:     StorageClass: C_NULL (0x0)
+# CASE2-NEXT:     NumberOfAuxEntries: 0
+# CASE2-NEXT:   }
+# CASE2-NEXT:   Symbol {
+# CASE2-NEXT:     Index: 1
+# CASE2-NEXT:     Name: a
+# CASE2-NEXT:     Value: 0x0
+# CASE2-NEXT:     Section: N_UNDEF
+# CASE2-NEXT:     Type: 0x0
+# CASE2-NEXT:     StorageClass: C_NULL (0x0)
+# CASE2-NEXT:     NumberOfAuxEntries: 0
+# CASE2-NEXT:   }
+# CASE2-NEXT: ]
+# CASE2-NEXT: StringTable {
+# CASE2-NEXT:   Length (in bytes): 10
+# CASE2-NEXT:   [     4]   c
+# CASE2-NEXT:   [     6]   b
+# CASE2-NEXT:   [     8]   a
+# CASE2-NEXT: }
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x1DF
+Symbols:
+  - Name: text
+  - Name: alongname
+StringTable:
+  Length: 10
+  Strings:
+    - a
+    - b
+    - c
+
+## Case 3: symbol names that are not overwritten by specific values 
+##         will still be stored in string table.
+# RUN: yaml2obj --docnum=3 %s -o %t3
+# RUN: llvm-readobj %t3 --symbols --string-table | FileCheck %s --check-prefix=CASE3
+
+# CASE3:      Symbols [
+# CASE3-NEXT:   Symbol {
+# CASE3-NEXT:     Index: 0
+# CASE3-NEXT:     Name: b
+# CASE3-NEXT:     Value: 0x0
+# CASE3-NEXT:     Section: N_UNDEF
+# CASE3-NEXT:     Type: 0x0
+# CASE3-NEXT:     StorageClass: C_NULL (0x0)
+# CASE3-NEXT:     NumberOfAuxEntries: 0
+# CASE3-NEXT:   }
+# CASE3-NEXT:   Symbol {
+# CASE3-NEXT:     Index: 1
+# CASE3-NEXT:     Name: data
+# CASE3-NEXT:     Value: 0x0
+# CASE3-NEXT:     Section: N_UNDEF
+# CASE3-NEXT:     Type: 0x0
+# CASE3-NEXT:     StorageClass: C_NULL (0x0)
+# CASE3-NEXT:     NumberOfAuxEntries: 0
+# CASE3-NEXT:   }
+# CASE3-NEXT: ]
+# CASE3-NEXT: StringTable {
+# CASE3-NEXT:   Length (in bytes): 11
+# CASE3-NEXT:   [     4]   b
+# CASE3-NEXT:   [     6]   data
+# CASE3-NEXT: }
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x01F7
+Symbols:
+  - Name: text
+  - Name: data
+StringTable:
+  Strings:
+    - b
+
+## Case 4: no string table.
+# RUN: yaml2obj --docnum=4 %s -o %t4
+# RUN: llvm-readobj %t4 --string-table | FileCheck %s --check-prefix=CASE4
+
+# CASE4:      StringTable {
+# CASE4-NEXT:   Length (in bytes): 0
+# CASE4-NEXT: }
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x01F7
+
+## Case 5: suppress emission of string table.
+# RUN: yaml2obj --docnum=5 %s -o %t5
+
+## This case triggers an error (since the symbol names cannot be found 
+## from the string table).
+# RUN: not llvm-readobj %t5 --symbols 2>&1 | FileCheck %s --check-prefix=ERROR
+# ERROR: llvm-readobj: error: {{.*}}: Bad offset for string table entry
+
+# RUN: llvm-readobj %t5 --string-table | FileCheck %s --check-prefix=CASE5
+
+# CASE5:      StringTable {
+# CASE5-NEXT:   Length (in bytes): 0
+# CASE5-NEXT: }
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x01F7
+Symbols:
+  - Name: text
+StringTable:
+  Suppress: true