Floatover method has been proven a competitive installation technology in last thirty years. However, floatover installation is subject to a variety of technical challenges. Apart from weather restrictions, motions and position of the topside and deck transport vessel (DTV) should be strictly controlled during the entire installation operations. Therefore, a field monitoring system is essential to guarantee the installation safety. In this paper, a comprehensive introduction to the monitoring system developed by Shanghai Jiao Tong University is presented. The subsystems, including environment monitoring system, motions and position monitoring system, deck support units (DSUs) separating monitoring system, closed-circuit-television (CCTV) monitoring system as well as the integrated monitoring system (IMS), are proposed. Besides, the pre-installation surveys are also presented.