Since the introduction of QS9000, TS16949 and Six Sigma, process FMEA is widely used to improve the manufacturing process and build up control plans. However, it is seldom the case that a company gets complete benefits of the process FMEA. To overcome the problem and suggest a direction to follow, a maturity model of process FMEA is developed. The model is composed of critical 5 success factors and 46measurement items derived from experts`` opinion and similar models for 6 Sigma and quality management. The suitability of the model is proven by applying it to the Korean semiconductor manufacturers.