Abstract:An improved failure mode and effect analysis (FMEA) model was designed to analyze the potential failure modes and risks of the blended fuel engine. The FMEA model was established based on the fuzzy theory, grey relational analysis (GRA), and decision making trial and evaluation laboratory (DEMATEL). The experts’ qualitative evaluation was translated into quantitative index and was then used in the calculation of the risk priority number (RPN), relevancy degree, and reason degree. The rank of the calculation results showed the risk prioritizing of the blended fuel engine. Corresponding risk control recommendations were proposed.