The embodiment of the invention relates to the technical field of ultrasonic flaw detection, in particular to a probe coverage rate test method and apparatus, and an electronic device. In the method,when a probe moves in a chute along a set direction, first ultrasonic waves collected by a plurality of receiving channels of the probe can be obtained, a wave height curve chart is obtained accordingto the first ultrasonic waves and the position of the probe in the set direction, then a superposition margin of the probe is determined according to the wave height curve chart, and whether the coverage rate of the probe is qualified is judged according to the superposition margin. In this way, the first ultrasonic waves collected by the plurality of receiving channels that are in a working state at the same time can be obtained, so that the overlapping phenomenon of the plurality of receiving channels is taken into account, and the separate testing of the coverage rate of each receiving channel is avoided, as a result, accurate test of the coverage rate of the probe can be achieved, and whether the coverage rate of the probe is qualified can be accurately judged.