Handheld building radar flaw detector

The utility model discloses a handheld building radar flaw detector which comprises a handheld flaw detector, and the handheld flaw detector comprises a flaw detector body (1), a data display screen (2), a flaw detection head (3) and a control key (4), the data display screen is embedded in the upper part of the flaw detector body, the control key is embedded in a key groove (101) in the lower part of the flaw detector body, and the flaw detection head is arranged on the flaw detector body; a storage groove (103) is formed in the flaw detector body, the storage groove is located above the key groove, and a protection assembly (5) is arranged in the storage groove; the protection assembly comprises protection writing cloth (503) and a drawing mechanism, and the protection writing cloth is movably arranged on the flaw detector body through the drawing mechanism, so that the protection writing cloth can cover the control keys. The handheld ultrasonic flaw detector can solve the problems that a handheld ultrasoni