diff --git a/lib/irb.rb b/lib/irb.rb
index 6d9c96c8f..5cd13300e 100644
--- a/lib/irb.rb
+++ b/lib/irb.rb
@@ -180,6 +180,7 @@ def run(conf = IRB.conf)
         trap("SIGINT", prev_trap)
         conf[:AT_EXIT].each{|hook| hook.call}
 
+        context.io.restore_reline_settings if context.io.respond_to?(:restore_reline_settings)
         context.io.save_history if save_history
         Kernel.exit if forced_exit
       end
diff --git a/lib/irb/input-method.rb b/lib/irb/input-method.rb
index b9bbdeb1e..bc6c8f6dd 100644
--- a/lib/irb/input-method.rb
+++ b/lib/irb/input-method.rb
@@ -202,6 +202,8 @@ def initialize
       @eof = false
       @completor = RegexpCompletor.new
 
+      save_readline_settings
+
       if Readline.respond_to?("basic_word_break_characters=")
         Readline.basic_word_break_characters = BASIC_WORD_BREAK_CHARACTERS
       end
@@ -212,6 +214,25 @@ def initialize
       }
     end
 
+    def save_readline_settings
+      @original_readline_settings = {}
+      if Readline.respond_to?("basic_word_break_characters")
+        @original_readline_settings[:basic_word_break_characters] = Readline.basic_word_break_characters
+      end
+      @original_readline_settings[:completion_append_character] = Readline.completion_append_character
+      @original_readline_settings[:completion_proc] = Readline.completion_proc
+    end
+
+    def restore_reline_settings
+      return if !@original_readline_settings || @original_readline_settings.empty?
+
+      if @original_readline_settings.key?(:basic_word_break_characters) && Readline.respond_to?("basic_word_break_characters=")
+        Readline.basic_word_break_characters = @original_readline_settings[:basic_word_break_characters]
+      end
+      Readline.completion_append_character = @original_readline_settings[:completion_append_character]
+      Readline.completion_proc = @original_readline_settings[:completion_proc]
+    end
+
     def completion_info
       'RegexpCompletor'
     end
@@ -265,6 +286,8 @@ def initialize(completor)
       @eof = false
       @completor = completor
 
+      save_reline_settings
+
       Reline.basic_word_break_characters = BASIC_WORD_BREAK_CHARACTERS
       Reline.completion_append_character = nil
       Reline.completer_quote_characters = ''
@@ -288,6 +311,30 @@ def initialize(completor)
       end
     end
 
+    def save_reline_settings
+      @original_reline_settings = {
+        basic_word_break_characters: Reline.basic_word_break_characters,
+        completion_append_character: Reline.completion_append_character,
+        completer_quote_characters: Reline.completer_quote_characters,
+        completion_proc: Reline.completion_proc,
+        output_modifier_proc: Reline.output_modifier_proc,
+        dig_perfect_match_proc: Reline.dig_perfect_match_proc,
+        autocompletion: Reline.autocompletion
+      }
+    end
+
+    def restore_reline_settings
+      return unless @original_reline_settings
+
+      Reline.basic_word_break_characters = @original_reline_settings[:basic_word_break_characters]
+      Reline.completion_append_character = @original_reline_settings[:completion_append_character]
+      Reline.completer_quote_characters = @original_reline_settings[:completer_quote_characters]
+      Reline.completion_proc = @original_reline_settings[:completion_proc]
+      Reline.output_modifier_proc = @original_reline_settings[:output_modifier_proc]
+      Reline.dig_perfect_match_proc = @original_reline_settings[:dig_perfect_match_proc]
+      Reline.autocompletion = @original_reline_settings[:autocompletion]
+    end
+
     def completion_info
       autocomplete_message = Reline.autocompletion ? 'Autocomplete' : 'Tab Complete'
       "#{autocomplete_message}, #{@completor.inspect}"
diff --git a/test/irb/test_reline_global_leak.rb b/test/irb/test_reline_global_leak.rb
new file mode 100644
index 000000000..dbf948325
--- /dev/null
+++ b/test/irb/test_reline_global_leak.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+require "irb"
+require_relative "helper"
+
+module TestIRB
+  class RelineGlobalLeakTest < IntegrationTestCase
+    def test_reline_autocompletion_is_restored_after_irb_exit
+      write_ruby <<~'RUBY'
+        require 'reline'
+
+        Reline.autocompletion = false
+        puts "Before: #{Reline.autocompletion}"
+
+        binding.irb
+
+        puts "After: #{Reline.autocompletion}"
+      RUBY
+
+      output = run_ruby_file do
+        type "exit"
+      end
+
+      assert_include output, "Before: false"
+      assert_include output, "After: false"
+    end
+  end
+end