diff --git a/openmp/README.rst b/openmp/README.rst
--- a/openmp/README.rst
+++ b/openmp/README.rst
@@ -165,6 +165,12 @@
 **LIBOMP_FORTRAN_MODULES** = ``OFF|ON``
   Create the Fortran modules (requires Fortran compiler).
 
+  .. note::
+
+  If libomptarget is built in-tree with both flang and openmp in
+  `LLVM_ENABLE_PROJECTS`, flang will be used for Fortran offloading
+  tests.
+
 macOS* Fat Libraries
 """"""""""""""""""""
 On macOS* machines, it is possible to build universal (or fat) libraries which
diff --git a/openmp/libomptarget/test/CMakeLists.txt b/openmp/libomptarget/test/CMakeLists.txt
--- a/openmp/libomptarget/test/CMakeLists.txt
+++ b/openmp/libomptarget/test/CMakeLists.txt
@@ -32,9 +32,13 @@
   configure_file(lit.site.cfg.in ${CURRENT_TARGET}/lit.site.cfg @ONLY)
 endforeach()
 
+if ("flang" IN_LIST LLVM_ENABLE_PROJECTS)
+  SET(FORTRAN_TEST_DEPS flang-new)
+endif()
+
 add_openmp_testsuite(check-libomptarget
   "Running libomptarget tests"
   ${LIBOMPTARGET_LIT_TESTSUITES}
   EXCLUDE_FROM_CHECK_ALL
-  DEPENDS omptarget omp ${LIBOMPTARGET_TESTED_PLUGINS}
+  DEPENDS omptarget omp ${LIBOMPTARGET_TESTED_PLUGINS} ${FORTRAN_TEST_DEPS}
   ARGS ${LIBOMPTARGET_LIT_ARG_LIST})
diff --git a/openmp/libomptarget/test/lit.cfg b/openmp/libomptarget/test/lit.cfg
--- a/openmp/libomptarget/test/lit.cfg
+++ b/openmp/libomptarget/test/lit.cfg
@@ -4,6 +4,10 @@
 import os
 import lit.formats
 
+from lit.llvm import llvm_config
+from lit.llvm.subst import ToolSubst
+from lit.llvm.subst import FindTool
+
 # Tell pylint that we know config and lit_config exist somewhere.
 if 'PYLINT_IMPORT' in os.environ:
     config = object()
@@ -58,6 +62,8 @@
 # test_exec_root: The root object directory where output is placed
 config.test_exec_root = config.libomptarget_obj_root
 
+tools = []
+
 # test format
 config.test_format = lit.formats.ShTest()
 
@@ -86,6 +92,10 @@
 
 config.available_features.add(config.libomptarget_current_target)
 
+if 'flang' in config.llvm_enabled_projects:
+  config.available_features.add('flang')
+  tools.append(ToolSubst('%flang', command=FindTool('flang-new'), unresolved='fatal'))
+
 # Determine whether the test system supports unified memory.
 # For CUDA, this is the case with compute capability 70 (Volta) or higher.
 # For all other targets, we currently assume it is.
@@ -302,3 +312,4 @@
     config.substitutions.append(("%cuda_flags", ""))
 config.substitutions.append(("%flags", config.test_flags))
 config.substitutions.append(("%not", config.libomptarget_not))
+llvm_config.add_tool_substitutions(tools, config.bin_llvm_tools_dir)
diff --git a/openmp/libomptarget/test/lit.site.cfg.in b/openmp/libomptarget/test/lit.site.cfg.in
--- a/openmp/libomptarget/test/lit.site.cfg.in
+++ b/openmp/libomptarget/test/lit.site.cfg.in
@@ -1,5 +1,6 @@
 @AUTO_GEN_COMMENT@
 
+config.bin_llvm_tools_dir = "@CMAKE_BINARY_DIR@/bin"
 config.test_c_compiler = "@OPENMP_TEST_C_COMPILER@"
 config.test_cxx_compiler = "@OPENMP_TEST_CXX_COMPILER@"
 config.test_compiler_features = @OPENMP_TEST_COMPILER_FEATURES@
@@ -20,6 +21,10 @@
 config.libomptarget_not = "@OPENMP_NOT_EXECUTABLE@"
 config.libomptarget_debug = @LIBOMPTARGET_DEBUG@
 config.has_libomptarget_ompt = @LIBOMPTARGET_OMPT_SUPPORT@
+config.llvm_enabled_projects = "@LLVM_ENABLE_PROJECTS@".split(";")
+
+import lit.llvm
+lit.llvm.initialize(lit_config, config)
 
 # Let the main config do the real work.
 lit_config.load_config(config, "@CMAKE_CURRENT_SOURCE_DIR@/lit.cfg")
diff --git a/openmp/libomptarget/test/offloading/fortran/basic_array.c b/openmp/libomptarget/test/offloading/fortran/basic_array.c
new file mode 100644
--- /dev/null
+++ b/openmp/libomptarget/test/offloading/fortran/basic_array.c
@@ -0,0 +1,43 @@
+// Basic offloading test for function compiled with flang
+// REQUIRES: flang, amdgcn-amd-amdhsa
+
+// RUN: %flang -c -fopenmp -fopenmp-targets=amdgcn-amd-amdhsa \
+// RUN:   %S/basic_array.f90 -o basic_array.o
+// RUN: %libomptarget-compile-generic basic_array.o
+// RUN: %t | %fcheck-generic
+
+#include <stdio.h>
+#define TEST_ARR_LEN 10
+
+#pragma omp declare target
+void increment_at(int i, int *array);
+#pragma omp end declare target
+
+void increment_array(int *b, int n) {
+#pragma omp target map(tofrom : b [0:n])
+  for (int i = 0; i < n; i++) {
+    increment_at(i, b);
+  }
+}
+
+int main() {
+  int arr[TEST_ARR_LEN] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
+
+  increment_array(arr, TEST_ARR_LEN);
+  for (int i = 0; i < TEST_ARR_LEN; i++) {
+    printf("%d = %d\n", i, arr[i]);
+  }
+
+  return 0;
+}
+
+// CHECK: 0 = 1
+// CHECK-NEXT: 1 = 2
+// CHECK-NEXT: 2 = 3
+// CHECK-NEXT: 3 = 4
+// CHECK-NEXT: 4 = 5
+// CHECK-NEXT: 5 = 6
+// CHECK-NEXT: 6 = 7
+// CHECK-NEXT: 7 = 8
+// CHECK-NEXT: 8 = 9
+// CHECK-NEXT: 9 = 10
diff --git a/openmp/libomptarget/test/offloading/fortran/basic_array.f90 b/openmp/libomptarget/test/offloading/fortran/basic_array.f90
new file mode 100644
--- /dev/null
+++ b/openmp/libomptarget/test/offloading/fortran/basic_array.f90
@@ -0,0 +1,6 @@
+subroutine increment_at(c_index, arr) bind(C, name="increment_at")
+    use ISO_C_BINDING
+    integer (C_INT), dimension(*), intent(inout) :: arr
+    integer (C_INT), value :: c_index
+    arr(c_index+1) = arr(c_index+1) + 1
+end subroutine