diff --git a/test/ruby/test_fiber.rb b/test/ruby/test_fiber.rb
index a7ed9ac7e0..947e75aa2c 100644
--- a/test/ruby/test_fiber.rb
+++ b/test/ruby/test_fiber.rb
@@ -50,7 +50,7 @@ class TestFiber < Test::Unit::TestCase
   end
 
   def test_many_fibers_with_threads
-    assert_normal_exit <<-SRC, timeout: 60
+    assert_normal_exit <<-SRC, timeout: 180
       max = 1000
       @cnt = 0
       (1..100).map{|ti|