diff --git a/R/pkg/R/utils.R b/R/pkg/R/utils.R
index d78c0a7a539a8..0c34a2910f5bc 100644
--- a/R/pkg/R/utils.R
+++ b/R/pkg/R/utils.R
@@ -630,7 +630,7 @@ convertNamedListToEnv <- function(namedList) {
 
   env <- new.env()
   for (name in names) {
-    env[[name]] <- namedList[[name]]
+    env[[name]] <- as.character(namedList[[name]])
   }
   env
 }