diff --git a/test/test_plugin.sh.in b/test/test_plugin.sh.in
index 02ac21f0eb..1d04760fb3 100644
--- a/test/test_plugin.sh.in
+++ b/test/test_plugin.sh.in
@@ -109,7 +109,7 @@ if [ $? != 0 ]; then
 fi
 
 # Set plugin path
-ENVCMD="env HDF5_PLUGIN_PATH=${TEMP_PLUGIN_DIR}:${TEMP_FILTER_DIR1}:${TEMP_FILTER_DIR2}"
+ENVCMD="env HDF5_PLUGIN_PATH=${TEMP_PLUGIN_DIR}:${TEMP_FILTER_DIR1}:${TEMP_FILTER_DIR2}:${HDF5_PLUGIN_PATH}"
 
 # Run the tests
 $ENVCMD $FILTER_TEST_BIN
diff --git a/tools/test/h5diff/h5diff_plugin.sh.in b/tools/test/h5diff/h5diff_plugin.sh.in
index ee7bc8bdf7..e3f0f01314 100644
--- a/tools/test/h5diff/h5diff_plugin.sh.in
+++ b/tools/test/h5diff/h5diff_plugin.sh.in
@@ -82,7 +82,7 @@ if [ $? != 0 ]; then
 fi
 
 # setup plugin path
-ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}"
+ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}:${HDF5_PLUGIN_PATH}"
 
 #
 # copy test files and expected output files from source dirs to test dir
diff --git a/tools/test/h5dump/h5dump_plugin.sh.in b/tools/test/h5dump/h5dump_plugin.sh.in
index b2f9f31b4a..d9b77ee101 100644
--- a/tools/test/h5dump/h5dump_plugin.sh.in
+++ b/tools/test/h5dump/h5dump_plugin.sh.in
@@ -88,7 +88,7 @@ if [ $? != 0 ]; then
 fi
 
 # setup plugin path
-ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}"
+ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}:${HDF5_PLUGIN_PATH}"
 
 #
 # copy test files and expected output files from source dirs to test dir
diff --git a/tools/test/h5ls/h5ls_plugin.sh.in b/tools/test/h5ls/h5ls_plugin.sh.in
index 48f6e1eb15..02e0cf7c49 100644
--- a/tools/test/h5ls/h5ls_plugin.sh.in
+++ b/tools/test/h5ls/h5ls_plugin.sh.in
@@ -88,7 +88,7 @@ if [ $? != 0 ]; then
 fi
 
 # setup plugin path
-ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}"
+ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}:${HDF5_PLUGIN_PATH}"
 
 #
 # copy test files and expected output files from source dirs to test dir
diff --git a/tools/test/h5repack/h5repack_plugin.sh.in b/tools/test/h5repack/h5repack_plugin.sh.in
index 14bcbbf817..bd7c3a1229 100644
--- a/tools/test/h5repack/h5repack_plugin.sh.in
+++ b/tools/test/h5repack/h5repack_plugin.sh.in
@@ -98,7 +98,7 @@ if [ $? != 0 ]; then
 fi
 
 # setup plugin path
-ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}"
+ENVCMD="env HDF5_PLUGIN_PATH=../${PLUGIN_LIBDIR}:${HDF5_PLUGIN_PATH}"
 
 COPY_TESTFILES_TO_TESTDIR()
 {