diff --git a/var/spack/repos/builtin/packages/libzmq/package.py b/var/spack/repos/builtin/packages/libzmq/package.py
index dac309b6993..5cd098b6c4c 100644
--- a/var/spack/repos/builtin/packages/libzmq/package.py
+++ b/var/spack/repos/builtin/packages/libzmq/package.py
@@ -100,7 +100,7 @@ def configure_args(self):
         config_args.extend(self.enable_or_disable("libunwind"))
 
         if "+libsodium" in self.spec:
-            config_args.append("--with-libsodium")
+            config_args.append("--with-libsodium=" + self.spec["libsodium"].prefix)
         if "~docs" in self.spec:
             config_args.append("--without-docs")
         if "clang" in self.compiler.cc: