diff --git a/lib/github_changelog_generator/octo_fetcher.rb b/lib/github_changelog_generator/octo_fetcher.rb
index 57f70914d..9fdfe1221 100644
--- a/lib/github_changelog_generator/octo_fetcher.rb
+++ b/lib/github_changelog_generator/octo_fetcher.rb
@@ -187,12 +187,14 @@ def fetch_closed_pull_requests
     def fetch_events_async(issues)
       i       = 0
       threads = []
+      # Add accept option explicitly for disabling the warning of preview API.
+      preview = { accept: Octokit::Preview::PREVIEW_TYPES[:project_card_events] }
 
       issues.each_slice(MAX_THREAD_NUMBER) do |issues_slice|
         issues_slice.each do |issue|
           threads << Thread.new do
             issue["events"] = []
-            iterate_pages(@client, "issue_events", issue["number"]) do |new_event|
+            iterate_pages(@client, "issue_events", issue["number"], preview) do |new_event|
               issue["events"].concat(new_event)
             end
             issue["events"] = issue["events"].map { |event| stringify_keys_deep(event.to_hash) }