diff --git a/lib/rbs/collection/config/lockfile_generator.rb b/lib/rbs/collection/config/lockfile_generator.rb
index c59dc31be..7b82b5cf9 100644
--- a/lib/rbs/collection/config/lockfile_generator.rb
+++ b/lib/rbs/collection/config/lockfile_generator.rb
@@ -16,7 +16,6 @@ class LockfileGenerator
           "benchmark" => nil,
           "bigdecimal" => ">= 4.1.0",
           "csv" => nil,
-          "kconv" => nil,
           "logger" => nil,
           "minitest" => nil,
           "net-smtp" => nil,