diff --git a/spec/parallel_tests_spec.rb b/spec/parallel_tests_spec.rb
index a89d279b..fe9fdcdb 100644
--- a/spec/parallel_tests_spec.rb
+++ b/spec/parallel_tests_spec.rb
@@ -184,7 +184,8 @@ def with_running_processes(count, wait=0.2)
   end
 
   describe ".stop_all_processes" do
-    it 'kills the running child process' do
+    # Process.kill on Windows doesn't work as expected. It kills all process group instead of just one process.
+    it 'kills the running child process', unless: Gem.win_platform? do
       ParallelTests.pids.send(:clear)
       Thread.new do
         ParallelTests::Test::Runner.execute_command('sleep 3', 1, 1, {})