diff --git a/flang/lib/Parser/openmp-parsers.cpp b/flang/lib/Parser/openmp-parsers.cpp
--- a/flang/lib/Parser/openmp-parsers.cpp
+++ b/flang/lib/Parser/openmp-parsers.cpp
@@ -218,8 +218,8 @@
                      parenthesized(Parser<OmpObjectList>{}))) ||
     "PROC_BIND" >> construct<OmpClause>(construct<OmpClause::ProcBind>(
                        parenthesized(Parser<OmpProcBindClause>{}))) ||
-    "REDUCTION" >>
-        construct<OmpClause>(parenthesized(Parser<OmpReductionClause>{})) ||
+    "REDUCTION" >> construct<OmpClause>(construct<OmpClause::Reduction>(
+                       parenthesized(Parser<OmpReductionClause>{}))) ||
     "TASK_REDUCTION" >>
         construct<OmpClause>(construct<OmpClause::TaskReduction>(
             parenthesized(Parser<OmpReductionClause>{}))) ||
diff --git a/flang/lib/Parser/unparse.cpp b/flang/lib/Parser/unparse.cpp
--- a/flang/lib/Parser/unparse.cpp
+++ b/flang/lib/Parser/unparse.cpp
@@ -2013,11 +2013,9 @@
     Put(")");
   }
   void Unparse(const OmpReductionClause &x) {
-    Word("REDUCTION(");
     Walk(std::get<OmpReductionOperator>(x.t));
     Put(":");
     Walk(std::get<OmpObjectList>(x.t));
-    Put(")");
   }
   void Unparse(const OmpAllocateClause &x) {
     Walk(std::get<std::optional<OmpAllocateClause::Allocator>>(x.t));
diff --git a/flang/lib/Semantics/check-omp-structure.h b/flang/lib/Semantics/check-omp-structure.h
--- a/flang/lib/Semantics/check-omp-structure.h
+++ b/flang/lib/Semantics/check-omp-structure.h
@@ -152,6 +152,7 @@
   void Enter(const parser::OmpClause::Priority &);
   void Enter(const parser::OmpClause::Private &);
   void Enter(const parser::OmpClause::ProcBind &);
+  void Enter(const parser::OmpClause::Reduction &);
   void Enter(const parser::OmpClause::Safelen &);
   void Enter(const parser::OmpClause::Shared &);
   void Enter(const parser::OmpClause::Simdlen &);
@@ -184,7 +185,6 @@
   void Enter(const parser::OmpIfClause &);
   void Enter(const parser::OmpLinearClause &);
   void Enter(const parser::OmpMapClause &);
-  void Enter(const parser::OmpReductionClause &);
   void Enter(const parser::OmpScheduleClause &);
 
 private:
diff --git a/flang/lib/Semantics/check-omp-structure.cpp b/flang/lib/Semantics/check-omp-structure.cpp
--- a/flang/lib/Semantics/check-omp-structure.cpp
+++ b/flang/lib/Semantics/check-omp-structure.cpp
@@ -419,6 +419,7 @@
 CHECK_SIMPLE_CLAUSE(Nogroup, OMPC_nogroup)
 CHECK_SIMPLE_CLAUSE(Notinbranch, OMPC_notinbranch)
 CHECK_SIMPLE_CLAUSE(Nowait, OMPC_nowait)
+CHECK_SIMPLE_CLAUSE(Reduction, OMPC_reduction)
 CHECK_SIMPLE_CLAUSE(TaskReduction, OMPC_task_reduction)
 CHECK_SIMPLE_CLAUSE(To, OMPC_to)
 CHECK_SIMPLE_CLAUSE(Uniform, OMPC_uniform)
@@ -495,7 +496,6 @@
   }
 }
 // Following clauses have a seperate node in parse-tree.h.
-CHECK_SIMPLE_PARSER_CLAUSE(OmpReductionClause, OMPC_reduction)
 // Atomic-clause
 CHECK_SIMPLE_PARSER_CLAUSE(OmpAtomicRead, OMPC_read)
 CHECK_SIMPLE_PARSER_CLAUSE(OmpAtomicWrite, OMPC_write)
diff --git a/llvm/include/llvm/Frontend/OpenMP/OMP.td b/llvm/include/llvm/Frontend/OpenMP/OMP.td
--- a/llvm/include/llvm/Frontend/OpenMP/OMP.td
+++ b/llvm/include/llvm/Frontend/OpenMP/OMP.td
@@ -82,7 +82,7 @@
 }
 def OMPC_Reduction : Clause<"reduction"> {
   let clangClass = "OMPReductionClause";
-  let flangClass = "OmpReductionClause";
+  let flangClassValue = "OmpReductionClause";
 }
 def OMPC_Linear : Clause<"linear"> {
   let clangClass = "OMPLinearClause";