In order to assess potential risks bridge static test, the equation which adopts the reliability theory that based on probability analysis was deduced to calculate the failure risk of the bridge and the static load test of single beam. The allowable reliability index of the static load test and the risk evaluation method which can be used for the static load test of new bridges, old bridges, elevated bridges and precast beams is proposed, as is illustrated with examples. This method is used to calculate the allowable values of the attenuation coefficient of resistance and the lifting coefficient of basic members, and to define the bridge range that should be evaluated by test. The effects of various influencing factors on the test reliability index were analyzed, and the structural reliability was compared when different test control load value methods were adopted. The results showed that the test reliability index of new bridge was directly proportional to the ratio of dead to live、dead (constructed) to dead (unconstructed). The former was the main factor, and the latter only affected when the ratio of dead to live was not more than 0.5. The decrease of resistance and the increase of vehicle load effect make the test reliability index decrease. When the resistance decreases by 30%, the average decrease of test reliability index is 1.4~2.3, and when the vehicle load effect increases by 50%, the average decrease of test reliability index is 0.7~1.1.