This study developed an algirithm for analyzing the safety of the boiler system including equipments and operating procedures using SMV (Symbolic Model Verifier). The strength of this algorithm is to verify the interactions of various variables simultaneously, while conventional simulation technique verifies only a few variable at one time. A boiler model is developed using SMV, and it can specify failures of fans, detectors and pumps. This method tests numerous dangerous conditions occured by multiple variables and identifies potential in the boiler system.