This paper proposes an intelligent monitoring system to adapt motorized high speed spindle on machine tools to meet the requirement of Industries 4.0, based on the techniques of power electronic engineering, mechatronics and reliability engineering. In this paper, a force-sensor-integrated spindle is proposed to monitor the bearing stress during operation. The implementation of charge amplifier and mechanical design are described as well. As a result, raw data is transmitted through a filter to create fruitful information and allow the remote monitoring system to operate effectively. The information supports predictive maintenance plans and improves the quality of after-sales service