Abstract: Based on the traditional LEC evaluation method and the comprehensive effects of "people,things, rings and tubes" analyzed on the possibility of accidents, four first-level indicators and twenty second-level indicators are determined, and the modified coefficient is introduced to reduce the effect of human subjectivity on the evaluation results. Combined with a project calculation case, it illustrates the necessity of amending the LEC evaluation method, and establishes a "4+3" risk control model according to the actual risk division results, so that the major risks in the implementation of a project can be effectively controlled.