diff --git a/test/kernel.rb b/test/kernel.rb
index 73996897..4ef1e94d 100644
--- a/test/kernel.rb
+++ b/test/kernel.rb
@@ -36,6 +36,8 @@
 		end
 		
 		it "can fail to execute child process" do
+			skip "JRuby does not spawn a missing command, so there is no process to wait for" if RUBY_ENGINE == "jruby"
+			
 			expect(reactor).to receive(:process_wait)
 			
 			result = ::Kernel.system("does-not-exist")
diff --git a/test/process/fork.rb b/test/process/fork.rb
index 5f67d490..c6e3429f 100644
--- a/test/process/fork.rb
+++ b/test/process/fork.rb
@@ -10,6 +10,8 @@
 describe Process do
 	describe ".fork" do
 		it "can fork with block form" do
+			skip "Process.fork is not supported!" unless Process.respond_to?(:fork)
+			
 			r, w = IO.pipe
 			
 			Async do
@@ -27,6 +29,8 @@
 		end
 		
 		it "can fork with non-block form" do
+			skip "Process.fork is not supported!" unless Process.respond_to?(:fork)
+			
 			r, w = IO.pipe
 			
 			Async do
@@ -46,6 +50,8 @@
 		end
 		
 		it "can fork while another fiber is blocked" do
+			skip "Process.fork is not supported!" unless Process.respond_to?(:fork)
+			
 			r, w = IO.pipe
 			queue = Thread::Queue.new