Abstract: In order to avoid drilling troubles and accidents,improve drilling efficiency and reduce drilling cost,the key technologies and real-time model composition in drilling risk control system were investigated.On the basis of analyzing the key technologies of NDS system,such as measurement-while-drilling,drilling risk management,geo-mechanical model,pore pressure prediction,3D visualization,real time monitoring by eDrilling drilling simulator,virtual wellbore,design,drilling,training and evaluation after drilling,drilling trouble prediction by Copilot system,the key technologies for drilling risk control system were determined,and the restrictions in studying it China were also pointed out.The key technologies mainly include measurement-while-drilling,data quality management,database management,real-time models,visualization,risk control software system and infrastructure.The real-time models include flow model,torque/drag model,vibration model,ROP model,wellbore stability model and geo-mechanical model.Definition of key technologies and specific description of real-time models can provide a good reference for developing drilling risk control system in China.