Handheld steel plate flaw detection device

The invention relates to the technical field of steel plate flaw detection, in particular to a handheld steel plate flaw detection device which comprises a positioning structure used for being matched with the edge of a to-be-detected steel plate and advancing along the edge of the steel plate, the positioning structure comprises a wheel carrier, and a positioning wheel set for forming a clamping structure for the steel plate is arranged on the wheel carrier; the wheel carrier is also connected with an adjusting structure for adjusting the advancing path of the flaw detection assembly; the flaw detection assembly comprises a flaw detection frame, and a plurality of ultrasonic detectors are arranged on the flaw detection frame at intervals in rows and columns; a gap is reserved between the ultrasonic detector and the to-be-detected surface; a liquid supply device is arranged on the flaw detection frame and is used for injecting a liquid medium into the gap; the handheld structure comprises an operating rod con