Abstract: By analyzing the overall configuration and working status of domestic offshore workover rigs, it is found that high labor intensity and safety risks as well as low degree of automation and intelligence are among the most prominent features of in-service offshore workover rigs. Traditional workover mode is gradually unable to meet the high requirements of modern operations. In view of this, the most automated and intelligent offshore workover rig system in China has been developed. The pipe handling equipment, driller control system, maintenance system as well as fire and gas system were mainly researched, designed and upgraded in this paper. A series of assembly and debugging were carried out at LSPE assembly site. Finally, the design and function of this workover rig system were verified through practical application at offshore platforms, which shows that this workover rig system has greatly changed traditional workover mode and improved the overall level of domestic offshore workover rigs. This application has provided valuable reference and guidance for future research and development of offshore workover rigs.