diff --git a/network/misc/protobuf/pspec.xml b/network/misc/protobuf/pspec.xml
index 55062ca1c4..b04f280625 100644
--- a/network/misc/protobuf/pspec.xml
+++ b/network/misc/protobuf/pspec.xml
@@ -27,6 +27,7 @@
         <Name>protobuf</Name>
         <Summary>Google's data interchange format</Summary>
         <RuntimeDependencies>
+            <Dependency>zlib</Dependency>
             <Dependency>libgcc</Dependency>
         </RuntimeDependencies>
         <Files>
@@ -140,4 +141,4 @@
             <Email>admins@pisilinux.org</Email>
         </Update>
     </History>
-</PISI>
\ No newline at end of file
+</PISI>