diff --git a/test/ruby/test_process.rb b/test/ruby/test_process.rb
index 45af7ae1f7..a0b08dd110 100644
--- a/test/ruby/test_process.rb
+++ b/test/ruby/test_process.rb
@@ -1605,7 +1605,11 @@ class TestProcess < Test::Unit::TestCase
       Process.wait pid
       assert sig_r.wait_readable(5), 'self-pipe not readable'
     end
-    assert_equal [true], signal_received, " [ruby-core:19744]"
+    if RubyVM::MJIT.enabled?  # MJIT may trigger extra SIGCHLD
+      assert_equal [true], signal_received.uniq, "[ruby-core:19744]"
+    else
+      assert_equal [true], signal_received, "[ruby-core:19744]"
+    end
   rescue NotImplementedError, ArgumentError
   ensure
     begin