diff --git a/clang/docs/ClangFormatStyleOptions.rst b/clang/docs/ClangFormatStyleOptions.rst
--- a/clang/docs/ClangFormatStyleOptions.rst
+++ b/clang/docs/ClangFormatStyleOptions.rst
@@ -2615,6 +2615,20 @@
         }
      }
 
+**PPIndentWidth** (``unsigned``)
+  The number of columns to use for indentation of preprocessor statements.
+  When set to -1 this defaults to IndentWidth for backwards compatibility.
+
+  .. code-block:: c++
+
+     PPIndentWidth: 1
+
+     #ifdef __linux__
+     # define FOO
+     #else
+     # define BAR
+     #endif
+
 **IndentWrappedFunctionNames** (``bool``)
   Indent if a function definition or declaration is wrapped after the
   type.
diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -2659,6 +2659,19 @@
   /// Pointer and reference alignment style.
   PointerAlignmentStyle PointerAlignment;
 
+  /// The number of columns to use for indentation of preprocessor statements.
+  /// When set to -1 this defaults to IndentWidth for backwards compatibility.
+  /// \code
+  ///    PPIndentWidth: 1
+  ///
+  ///    #ifdef __linux__
+  ///    # define FOO
+  ///    #else
+  ///    # define BAR
+  ///    #endif
+  /// \endcode
+  signed PPIndentWidth;
+
   /// See documentation of ``RawStringFormats``.
   struct RawStringFormat {
     /// The language of this raw string.
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -664,6 +664,7 @@
     IO.mapOptional("PenaltyIndentedWhitespace",
                    Style.PenaltyIndentedWhitespace);
     IO.mapOptional("PointerAlignment", Style.PointerAlignment);
+    IO.mapOptional("PPIndentWidth", Style.PPIndentWidth);
     IO.mapOptional("RawStringFormats", Style.RawStringFormats);
     IO.mapOptional("ReflowComments", Style.ReflowComments);
     IO.mapOptional("ShortNamespaceLines", Style.ShortNamespaceLines);
@@ -1021,6 +1022,7 @@
   LLVMStyle.IndentRequires = false;
   LLVMStyle.IndentWrappedFunctionNames = false;
   LLVMStyle.IndentWidth = 2;
+  LLVMStyle.PPIndentWidth = -1;
   LLVMStyle.InsertTrailingCommas = FormatStyle::TCS_None;
   LLVMStyle.JavaScriptQuotes = FormatStyle::JSQS_Leave;
   LLVMStyle.JavaScriptWrapImports = true;
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -57,7 +57,9 @@
     while (IndentForLevel.size() <= Line.Level)
       IndentForLevel.push_back(-1);
     if (Line.InPPDirective) {
-      Indent = Line.Level * Style.IndentWidth + AdditionalIndent;
+      unsigned IndentWidth =
+          (Style.PPIndentWidth >= 0) ? Style.PPIndentWidth : Style.IndentWidth;
+      Indent = Line.Level * IndentWidth + AdditionalIndent;
     } else {
       IndentForLevel.resize(Line.Level + 1);
       Indent = getIndent(IndentForLevel, Line.Level);
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -3431,6 +3431,48 @@
   verifyFormat("a\f\\");
 }
 
+TEST_F(FormatTest, IndentsPPDirectiveWithPPIndentWidth) {
+  FormatStyle style = getChromiumStyle(FormatStyle::LK_Cpp);
+  style.IndentWidth = 4;
+  style.PPIndentWidth = 1;
+
+  style.IndentPPDirectives = FormatStyle::PPDIS_None;
+  verifyFormat("#ifdef __linux__\n"
+               "void foo() {\n"
+               "    int x = 0;\n"
+               "}\n"
+               "#define FOO\n"
+               "#endif\n"
+               "void bar() {\n"
+               "    int y = 0;\n"
+               "}\n",
+               style);
+
+  style.IndentPPDirectives = FormatStyle::PPDIS_AfterHash;
+  verifyFormat("#ifdef __linux__\n"
+               "void foo() {\n"
+               "    int x = 0;\n"
+               "}\n"
+               "# define FOO foo\n"
+               "#endif\n"
+               "void bar() {\n"
+               "    int y = 0;\n"
+               "}\n",
+               style);
+
+  style.IndentPPDirectives = FormatStyle::PPDIS_BeforeHash;
+  verifyFormat("#ifdef __linux__\n"
+               "void foo() {\n"
+               "    int x = 0;\n"
+               "}\n"
+               " #define FOO foo\n"
+               "#endif\n"
+               "void bar() {\n"
+               "    int y = 0;\n"
+               "}\n",
+               style);
+}
+
 TEST_F(FormatTest, IndentsPPDirectiveInReducedSpace) {
   verifyFormat("#define A(BB)", getLLVMStyleWithColumns(13));
   verifyFormat("#define A( \\\n    BB)", getLLVMStyleWithColumns(12));