diff --git a/app/controllers/category_hashtags_controller.rb b/app/controllers/category_hashtags_controller.rb
index ca4a1f70062..e779391f374 100644
--- a/app/controllers/category_hashtags_controller.rb
+++ b/app/controllers/category_hashtags_controller.rb
@@ -3,7 +3,6 @@ class CategoryHashtagsController < ApplicationController
 
   def check
     category_slugs = params[:category_slugs]
-    category_slugs.each(&:downcase!)
 
     ids = category_slugs.map { |category_slug| Category.query_from_hashtag_slug(category_slug).try(:id) }
 
diff --git a/spec/components/concern/category_hashtag_spec.rb b/spec/components/concern/category_hashtag_spec.rb
index be60931f795..c57ac891633 100644
--- a/spec/components/concern/category_hashtag_spec.rb
+++ b/spec/components/concern/category_hashtag_spec.rb
@@ -22,5 +22,13 @@ describe CategoryHashtag do
     it "should return nil for incorrect parent and child category slug" do
       expect(Category.query_from_hashtag_slug("random-slug#{CategoryHashtag::SEPARATOR}random-slug")).to eq(nil)
     end
+
+    it "should be case sensitive" do
+      parent_category.update_attributes!(slug: "ApPlE")
+      child_category.update_attributes!(slug: "OraNGE")
+
+      expect(Category.query_from_hashtag_slug("apple")).to eq(nil)
+      expect(Category.query_from_hashtag_slug("apple:orange")).to eq(nil)
+    end
   end
 end