Index: flang/include/flang/Lower/PFTBuilder.h
===================================================================
--- flang/include/flang/Lower/PFTBuilder.h
+++ flang/include/flang/Lower/PFTBuilder.h
@@ -141,6 +141,9 @@
 using DeclConstructs = std::tuple<parser::OpenMPDeclarativeConstruct,
                                   parser::OpenACCDeclarativeConstruct>;
 
+using OMPACCDirectives =
+    std::tuple<parser::OpenACCConstruct, parser::OpenMPConstruct>;
+
 template <typename A>
 static constexpr bool isActionStmt{common::HasMember<A, ActionStmts>};
 
@@ -162,6 +165,9 @@
 template <typename A>
 static constexpr bool isDeclConstruct{common::HasMember<A, DeclConstructs>};
 
+template <typename A>
+static constexpr bool isOMPACCDirective{common::HasMember<A, OMPACCDirectives>};
+
 template <typename A>
 static constexpr bool isIntermediateConstructStmt{common::HasMember<
     A, std::tuple<parser::CaseStmt, parser::ElseIfStmt, parser::ElseStmt,
@@ -251,6 +257,11 @@
     return visit(common::visitors{
         [](auto &r) { return pft::isDirective<std::decay_t<decltype(r)>>; }});
   }
+  constexpr bool isOMPACCDirective() const {
+    return visit(common::visitors{[](auto &r) {
+      return pft::isOMPACCDirective<std::decay_t<decltype(r)>>;
+    }});
+  }
   constexpr bool isNopConstructStmt() const {
     return visit(common::visitors{[](auto &r) {
       return pft::isNopConstructStmt<std::decay_t<decltype(r)>>;
Index: flang/include/flang/Lower/Runtime.h
===================================================================
--- flang/include/flang/Lower/Runtime.h
+++ flang/include/flang/Lower/Runtime.h
@@ -53,7 +53,7 @@
 void genEventWaitStatement(AbstractConverter &, const parser::EventWaitStmt &);
 void genLockStatement(AbstractConverter &, const parser::LockStmt &);
 void genFailImageStatement(AbstractConverter &);
-void genStopStatement(AbstractConverter &, const parser::StopStmt &);
+void genStopStatement(AbstractConverter &, const parser::StopStmt &, bool);
 void genSyncAllStatement(AbstractConverter &, const parser::SyncAllStmt &);
 void genSyncImagesStatement(AbstractConverter &,
                             const parser::SyncImagesStmt &);
Index: flang/lib/Lower/Bridge.cpp
===================================================================
--- flang/lib/Lower/Bridge.cpp
+++ flang/lib/Lower/Bridge.cpp
@@ -3313,7 +3313,10 @@
 
   // call STOP, ERROR STOP in runtime
   void genFIR(const Fortran::parser::StopStmt &stmt) {
-    genStopStatement(*this, stmt);
+    bool hasAttachedUnreachable =
+        !getEval().parentConstruct ||
+        !getEval().parentConstruct->isOMPACCDirective();
+    genStopStatement(*this, stmt, hasAttachedUnreachable);
   }
 
   void genFIR(const Fortran::parser::ReturnStmt &stmt) {
Index: flang/lib/Lower/Runtime.cpp
===================================================================
--- flang/lib/Lower/Runtime.cpp
+++ flang/lib/Lower/Runtime.cpp
@@ -42,7 +42,7 @@
 
 void Fortran::lower::genStopStatement(
     Fortran::lower::AbstractConverter &converter,
-    const Fortran::parser::StopStmt &stmt) {
+    const Fortran::parser::StopStmt &stmt, bool hasAttachedUnreachable = true) {
   fir::FirOpBuilder &builder = converter.getFirOpBuilder();
   mlir::Location loc = converter.getCurrentLocation();
   Fortran::lower::StatementContext stmtCtx;
@@ -106,7 +106,8 @@
   }
 
   builder.create<fir::CallOp>(loc, callee, operands);
-  genUnreachable(builder, loc);
+  if (hasAttachedUnreachable)
+    genUnreachable(builder, loc);
 }
 
 void Fortran::lower::genFailImageStatement(
Index: flang/test/Lower/OpenACC/stop-stmt-in-region.f90
===================================================================
--- /dev/null
+++ flang/test/Lower/OpenACC/stop-stmt-in-region.f90
@@ -0,0 +1,41 @@
+! This test checks lowering of stop statement in OpenACC region.
+
+! RUN: bbc -fopenacc -emit-fir %s -o - | FileCheck %s
+! RUN: %flang_fc1 -emit-fir -fopenacc %s -o - | FileCheck %s
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region1() {
+! CHECK:         acc.parallel {
+! CHECK:           %[[VAL_0:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_1:.*]] = arith.constant false
+! CHECK:           %[[VAL_2:.*]] = arith.constant false
+! CHECK:           %[[VAL_3:.*]] = fir.call @_FortranAStopStatement(%[[VAL_0]], %[[VAL_1]], %[[VAL_2]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK:           acc.yield
+! CHECK:         }
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region1()
+  !$acc parallel
+    stop 1
+  !$acc end parallel
+end
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region2() {
+! CHECK:         %[[VAL_0:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFtest_stop_in_region2Ex"}
+! CHECK:         acc.parallel {
+! CHECK:           %[[VAL_1:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_2:.*]] = arith.constant false
+! CHECK:           %[[VAL_3:.*]] = arith.constant false
+! CHECK:           %[[VAL_4:.*]] = fir.call @_FortranAStopStatement(%[[VAL_1]], %[[VAL_2]], %[[VAL_3]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK:           acc.yield
+! CHECK:         }
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region2()
+  integer :: x
+  !$acc parallel
+    stop 1
+    x = 2
+  !$acc end parallel
+end
Index: flang/test/Lower/OpenMP/stop-stmt-in-region.f90
===================================================================
--- /dev/null
+++ flang/test/Lower/OpenMP/stop-stmt-in-region.f90
@@ -0,0 +1,117 @@
+! This test checks lowering of stop statement in OpenMP region.
+
+! RUN: bbc -fopenmp -emit-fir %s -o - | FileCheck %s
+! RUN: %flang_fc1 -emit-fir -fopenmp %s -o - | FileCheck %s
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region1() {
+! CHECK:         omp.parallel   {
+! CHECK:           %[[VAL_0:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_1:.*]] = arith.constant false
+! CHECK:           %[[VAL_2:.*]] = arith.constant false
+! CHECK:           %[[VAL_3:.*]] = fir.call @_FortranAStopStatement(%[[VAL_0]], %[[VAL_1]], %[[VAL_2]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK-NOT:       fir.unreachable
+! CHECK:           omp.terminator
+! CHECK:         }
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region1()
+  !$omp parallel
+    stop 1
+  !$omp end parallel
+end
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region2() {
+! CHECK:         %[[VAL_0:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFtest_stop_in_region2Ex"}
+! CHECK:         omp.parallel   {
+! CHECK:           %[[VAL_1:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_2:.*]] = arith.constant false
+! CHECK:           %[[VAL_3:.*]] = arith.constant false
+! CHECK:           %[[VAL_4:.*]] = fir.call @_FortranAStopStatement(%[[VAL_1]], %[[VAL_2]], %[[VAL_3]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK-NOT:       fir.unreachable
+! CHECK:           cf.br ^bb1
+! CHECK:         ^bb1:
+! CHECK:           %[[VAL_5:.*]] = arith.constant 2 : i32
+! CHECK:           fir.store %[[VAL_5]] to %[[VAL_0]] : !fir.ref<i32>
+! CHECK:           omp.terminator
+! CHECK:         }
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region2()
+  integer :: x
+  !$omp parallel
+    stop 1
+    x = 2
+  !$omp end parallel
+end
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region3() {
+! CHECK:         %[[VAL_0:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFtest_stop_in_region3Ex"}
+! CHECK:         omp.parallel   {
+! CHECK:           %[[VAL_1:.*]] = arith.constant 3 : i32
+! CHECK:           fir.store %[[VAL_1]] to %[[VAL_0]] : !fir.ref<i32>
+! CHECK:           %[[VAL_2:.*]] = fir.load %[[VAL_0]] : !fir.ref<i32>
+! CHECK:           %[[VAL_3:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_4:.*]] = arith.cmpi sgt, %[[VAL_2]], %[[VAL_3]] : i32
+! CHECK:           cf.cond_br %[[VAL_4]], ^bb1, ^bb2
+! CHECK:         ^bb1:
+! CHECK:           %[[VAL_5:.*]] = fir.load %[[VAL_0]] : !fir.ref<i32>
+! CHECK:           %[[VAL_6:.*]] = arith.constant false
+! CHECK:           %[[VAL_7:.*]] = arith.constant false
+! CHECK:           %[[VAL_8:.*]] = fir.call @_FortranAStopStatement(%[[VAL_5]], %[[VAL_6]], %[[VAL_7]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK:           fir.unreachable
+! CHECK:         ^bb2:
+! CHECK:           omp.terminator
+! CHECK:         }
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region3()
+  integer :: x
+  !$omp parallel
+    x = 3
+    if (x > 1) stop x
+  !$omp end parallel
+end
+
+! CHECK-LABEL: func.func @_QPtest_stop_in_region4() {
+! CHECK:         %[[VAL_0:.*]] = fir.alloca i32 {adapt.valuebyref}
+! CHECK:         %[[VAL_1:.*]] = fir.alloca i32 {bindc_name = "i", uniq_name = "_QFtest_stop_in_region4Ei"}
+! CHECK:         %[[VAL_2:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFtest_stop_in_region4Ex"}
+! CHECK:         %[[VAL_3:.*]] = arith.constant 1 : i32
+! CHECK:         %[[VAL_4:.*]] = arith.constant 10 : i32
+! CHECK:         %[[VAL_5:.*]] = arith.constant 1 : i32
+! CHECK:         omp.wsloop   for  (%[[VAL_6:.*]]) : i32 = (%[[VAL_3]]) to (%[[VAL_4]]) inclusive step (%[[VAL_5]]) {
+! CHECK:           fir.store %[[VAL_6]] to %[[VAL_0]] : !fir.ref<i32>
+! CHECK:           cf.br ^bb1
+! CHECK:         ^bb1:
+! CHECK:           %[[VAL_7:.*]] = arith.constant 3 : i32
+! CHECK:           fir.store %[[VAL_7]] to %[[VAL_2]] : !fir.ref<i32>
+! CHECK:           %[[VAL_8:.*]] = fir.load %[[VAL_2]] : !fir.ref<i32>
+! CHECK:           %[[VAL_9:.*]] = arith.constant 1 : i32
+! CHECK:           %[[VAL_10:.*]] = arith.cmpi sgt, %[[VAL_8]], %[[VAL_9]] : i32
+! CHECK:           cf.cond_br %[[VAL_10]], ^bb2, ^bb3
+! CHECK:         ^bb2:
+! CHECK:           %[[VAL_11:.*]] = fir.load %[[VAL_2]] : !fir.ref<i32>
+! CHECK:           %[[VAL_12:.*]] = arith.constant false
+! CHECK:           %[[VAL_13:.*]] = arith.constant false
+! CHECK:           %[[VAL_14:.*]] = fir.call @_FortranAStopStatement(%[[VAL_11]], %[[VAL_12]], %[[VAL_13]]) {{.*}} : (i32, i1, i1) -> none
+! CHECK:           fir.unreachable
+! CHECK:         ^bb3:
+! CHECK:           omp.yield
+! CHECK:         }
+! CHECK:         cf.br ^bb1
+! CHECK:       ^bb1:
+! CHECK:         return
+! CHECK:       }
+
+subroutine test_stop_in_region4()
+  integer :: x
+  !$omp do
+  do i = 1, 10
+    x = 3
+    if (x > 1) stop x
+  enddo
+  !$omp end do
+end