diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -2897,6 +2897,9 @@
             getCanonicalForwardRedeclChain(D2CXX);
         for (auto *R : Redecls) {
           auto *RI = cast<CXXRecordDecl>(R);
+          // Skip the declaration if injected type is already set.
+          if (isa<InjectedClassNameType>(RI->getTypeForDecl()))
+            continue;
           RI->setTypeForDecl(nullptr);
           // Below we create a new injected type and assign that to the
           // canonical decl, subsequent declarations in the chain will reuse
@@ -5393,16 +5396,16 @@
 
   CXXRecordDecl *FromTemplated = D->getTemplatedDecl();
 
+  auto TemplateParamsOrErr = import(D->getTemplateParameters());
+  if (!TemplateParamsOrErr)
+    return TemplateParamsOrErr.takeError();
+
   // Create the declaration that is being templated.
   CXXRecordDecl *ToTemplated;
   if (Error Err = importInto(ToTemplated, FromTemplated))
     return std::move(Err);
 
   // Create the class template declaration itself.
-  auto TemplateParamsOrErr = import(D->getTemplateParameters());
-  if (!TemplateParamsOrErr)
-    return TemplateParamsOrErr.takeError();
-
   ClassTemplateDecl *D2;
   if (GetImportedOrCreateDecl(D2, D, Importer.getToContext(), DC, Loc, Name,
                               *TemplateParamsOrErr, ToTemplated))
diff --git a/clang/unittests/AST/ASTImporterTest.cpp b/clang/unittests/AST/ASTImporterTest.cpp
--- a/clang/unittests/AST/ASTImporterTest.cpp
+++ b/clang/unittests/AST/ASTImporterTest.cpp
@@ -6141,6 +6141,41 @@
   EXPECT_EQ(ToAttr->getAnnotation(), "A");
 }
 
+TEST_P(ASTImporterOptionSpecificTestBase,
+       ImportOfTemplatedDeclWhenPreviousDeclHasNoDescribedTemplateSet) {
+  Decl *FromTU = getTuDecl(
+      R"(
+
+      namespace std {
+        template<typename T>
+        class basic_stringbuf;
+      }
+      namespace std {
+        class char_traits;
+        template<typename T = char_traits>
+        class basic_stringbuf;
+      }
+      namespace std {
+        template<typename T>
+        class basic_stringbuf {};
+      }
+
+      )",
+      Lang_CXX11);
+
+  auto *From1 = FirstDeclMatcher<ClassTemplateDecl>().match(
+      FromTU,
+      classTemplateDecl(hasName("basic_stringbuf"), unless(isImplicit())));
+  auto *To1 = cast_or_null<ClassTemplateDecl>(Import(From1, Lang_CXX11));
+  EXPECT_TRUE(To1);
+
+  auto *From2 = LastDeclMatcher<ClassTemplateDecl>().match(
+      FromTU,
+      classTemplateDecl(hasName("basic_stringbuf"), unless(isImplicit())));
+  auto *To2 = cast_or_null<ClassTemplateDecl>(Import(From2, Lang_CXX11));
+  EXPECT_TRUE(To2);
+}
+
 INSTANTIATE_TEST_CASE_P(ParameterizedTests, ASTImporterLookupTableTest,
                         DefaultTestValuesForRunOptions, );