With the characteristics of wide time span, engineer-toorder, advanced technology to be adopted etc., Complex product systems (CoPS) innovation becomes a systematic project full of risks. Risk evaluation is the vital role in life-cycle process of the CoPS. Furthermore, the technical risk is major factor leading to cost, time and effectiveness risk. Because of the non-structural features of CoPS, it is difficult to derive quantitative measurements of various technical risk of each stage during the whole life-cycle of the CoPS. To resolve this problem, firstly, the concepts of CoPS were analyzed, including technical risk and the relevant comprehensive integration, and then a qualitative and quantitative evaluation mechanism for technical risk evaluation has been developed. Consequently, the evaluation procedures and a sequence of steps were established. Finally, to clarify the feasibility and effectiveness of the evaluation model, the technical risk was evaluated for a complex product systems example.