diff --git a/nvm.sh b/nvm.sh
index 336760e..453df19 100644
--- a/nvm.sh
+++ b/nvm.sh
@@ -771,7 +771,7 @@ nvm_strip_iojs_prefix() {
   if [ "${1-}" = "${NVM_IOJS_PREFIX}" ]; then
     nvm_echo
   else
-    nvm_echo "${1#"${NVM_IOJS_PREFIX}"-}"
+    nvm_echo "${1#${NVM_IOJS_PREFIX}-}"
   fi
 }