diff --git a/src/libs/qmuparser/qmuparser.pro b/src/libs/qmuparser/qmuparser.pro
index 1c1e32709..f1f74ac6b 100644
--- a/src/libs/qmuparser/qmuparser.pro
+++ b/src/libs/qmuparser/qmuparser.pro
@@ -40,10 +40,15 @@ VERSION = 2.2.5
 # Set "make install" command for Unix-like systems.
 unix:!macx{
     isEmpty(PREFIX_LIB){
-        contains(QMAKE_HOST.arch, x86_64) {
-            PREFIX_LIB = $$DEFAULT_PREFIX/lib64
+        isEmpty(PREFIX){
+            PR_LIB = $$DEFAULT_PREFIX
         } else {
-            PREFIX_LIB = $$DEFAULT_PREFIX/lib
+            PR_LIB = $$PREFIX
+        }
+        contains(QMAKE_HOST.arch, x86_64) {
+            PREFIX_LIB = $$PR_LIB/lib64
+        } else {
+            PREFIX_LIB = $$PR_LIB/lib
         }
     }
     target.path = $$PREFIX_LIB
diff --git a/src/libs/vpropertyexplorer/vpropertyexplorer.pro b/src/libs/vpropertyexplorer/vpropertyexplorer.pro
index ab891e859..c7fab7c30 100644
--- a/src/libs/vpropertyexplorer/vpropertyexplorer.pro
+++ b/src/libs/vpropertyexplorer/vpropertyexplorer.pro
@@ -38,10 +38,15 @@ include(vpropertyexplorer.pri)
 # Set "make install" command for Unix-like systems.
 unix:!macx{
     isEmpty(PREFIX_LIB){
-        contains(QMAKE_HOST.arch, x86_64) {
-            PREFIX_LIB = $$DEFAULT_PREFIX/lib64
+        isEmpty(PREFIX){
+            PR_LIB = $$DEFAULT_PREFIX
         } else {
-            PREFIX_LIB = $$DEFAULT_PREFIX/lib
+            PR_LIB = $$PREFIX
+        }
+        contains(QMAKE_HOST.arch, x86_64) {
+            PREFIX_LIB = $$PR_LIB/lib64
+        } else {
+            PREFIX_LIB = $$PR_LIB/lib
         }
     }
     target.path = $$PREFIX_LIB