In order to overcome the drawback that the traditional risk priority number method could not clearly make a risk priority sequence, a new analysis method of RPN was presented. Combined with loss costs, this method was based on FMEA. Several quantitative parameters such as servicing time and costs were introduced to replace the three parameters used in the traditional method. And it took loss costs caused by failure as the final risk priority number, instead of severity of effects, probability occurrence and difficulty detection. Finally, safety evaluation to work equipment and other critical systems of a forklift was processed as a case to illustrate this proposed method. The results showed that the results processed by the new method could be utilized to solve the problem that the RPN values couldn't be sorted.