The work aims to study the weathering and safety degree of the dragon heads in Forbidden City by performing a nondestructive testing (NDT). The weathering indices (degree of surface weathering, cracks overview, pores, rebound strength, mass of powder) and safety level indices (crack property, specific values such as crack quantity, ultrasonic velocity, rebound strength) were obtained from non-destructive testing of 6 dragon head samples. Weathering and destructive tests were simulated in the laboratory, curvilinear relationship between bending strength, ultrasonic velocity and rebound strength was established. An evaluation system was built by means of Delphi method, weathering level and safety level of all dragon heads were obtained by means of weighted average method. Weathering level and safety conditions of 6 dragon heads were determined by fk=0.0004V0.4393R2.9302, a curve relation involving bending strength, ultrasound velocity and rebound strength of stone relics. The weathering level of component 2 was the weakest and safest. The safety condition of component 6 was the worst and effective precautionary measures should be taken timely. The nondestructive examination and health status evaluation method provided a simple, rapid and quantifiable method. The test results can be used in test and evaluation project of stony relics, so as to obtain the weathering and safety level of stony relics, and can be regarded as basis for decision-making of cultural relic management.