Safety-related coatings play an important role in passive nuclear power plants.The failure of coatings would affect the functional execution of the nuclear power plant safetysystem and nuclear safety. Domestic and foreign nuclear regulatory authorities attached greatimportance to the reliability and evaluation methods of safety-related coatings under simulatedaccident conditions. Based on the engineering application of safety-related coatings，the reliability and evaluation methods on simulated scenarios conditions of safety-related coatingfor passive nuclear power plants were studied. The results showed that the DBA（design basis accident）performance，dry film density，and thermal conductivity of the coatings should be considered comprehensively for the reliability of safety-related coatings in the simulationaccident conditions in a passive nuclear power plant. For engineering application of safety-related coating，it needed to be comprehensively evaluated from DBA performance，dry film density，thermal conductivity，coating fragments（quantity，size，position，and performance， etc.）， and debris margin after coating fragments enveloped to determine the reliability of coating under accident conditions，ensured that safety-related coatings under accident conditions did not affect system safety，and ensured safer，more efficient，and economical operation of the plant.