diff --git a/spec/rename_spec.cr b/spec/rename_spec.cr
index 6108974..c830581 100644
--- a/spec/rename_spec.cr
+++ b/spec/rename_spec.cr
@@ -68,4 +68,9 @@ describe Rule do
       .should eq "Ch. CH ID testing"
     rule.render({} of String => String).should eq "testing"
   end
+
+  it "escapes slash" do
+    rule = Rule.new "{id}"
+    rule.render({"id" => "/hello/world"}).should eq "_hello_world"
+  end
 end
diff --git a/src/rename.cr b/src/rename.cr
index 3aefcef..cd6af7b 100644
--- a/src/rename.cr
+++ b/src/rename.cr
@@ -135,7 +135,9 @@ module Rename
         else
           e.render hash
         end
-      end.join.strip
+      end.join
+        .strip
+        .gsub("/", "_")
     end
   end
 end