To improve production quality and reduce machining time, machining parameters need to be monitored and adjusted automatically in milling. An integrated controller which is modular, configurable and based on OMAC, is established. The hardware platform, resultant cutting force constraint and its fuzzy control rules have been introduced in detail. In the fuzzy controller designed, two inputs and one output are used with five fuzzy sets for the controller, and the output rate of feed-rate can be changed from 50% to 200%. This controller has the abilities of reducing fluctuation range of cutting force, adjusting feed-rate intelligently, which is a part of CNC system. The experiment results show it can realize the real time status monitoring with this system, reduce the cutting force fluctuation, and adjust the feed-rate intelligently during machining.