diff --git a/lib/net/http/exceptions.rb b/lib/net/http/exceptions.rb
index 0d34526616..933cd64ace 100644
--- a/lib/net/http/exceptions.rb
+++ b/lib/net/http/exceptions.rb
@@ -20,7 +20,15 @@ class Net::HTTPServerException < Net::ProtoServerError
   # We cannot use the name "HTTPServerError", it is the name of the response.
   include Net::HTTPExceptions
 end
+
+# for compatibility
+Net::HTTPClientException = Net::HTTPServerException
+
 class Net::HTTPFatalError < Net::ProtoFatalError
   include Net::HTTPExceptions
 end
 
+module Net
+  deprecate_constant(:HTTPServerException)
+  deprecate_constant(:ProtoServerError)
+end
diff --git a/test/net/http/test_httpresponse.rb b/test/net/http/test_httpresponse.rb
index d99c3611c5..29c38b2bc0 100644
--- a/test/net/http/test_httpresponse.rb
+++ b/test/net/http/test_httpresponse.rb
@@ -422,7 +422,7 @@ def test_raises_exception_with_missing_reason
 
     res = Net::HTTPResponse.read_new(io)
     assert_equal(nil, res.message)
-    assert_raise Net::HTTPServerException do
+    assert_raise Net::HTTPClientException do
       res.error!
     end
   end