The invention discloses a workblank grabbing intelligent mechanical arm used for the machining field. The workblank grabbing intelligent mechanical arm comprises a base and an upright column which is fixedly mounted at the upper end of the base; an ultrasonic flaw detector is arranged at the upper end of the upright column, and an upper computer is arranged on the side face of the ultrasonic flaw detector; a stepping motor is arranged at the upper end of the front face of the upright column, and a first electric hydraulic pushing rod is arranged on an output shaft of the stepping motor; a mounting rod is arranged at the lower end of the first electric hydraulic pushing rod, and a second electric hydraulic pushing rod is arranged in the middle of the side face of the mounting rod; and a grabbing hand is arranged at the lower end of the side face of the mounting rod. According to the workblank grabbing intelligent mechanical arm used for the machining field, non-destructive detecting can be conducted on a grabbed workblank piece, when defectiveness of the workblank piece is detected, the grabbing hand can automatically release the defective workblank piece; and when detecting is qualified, the workblank piece can be continuously transferred to the next process, so that non-destructive detecting does not need to be conducted independently, the process steps are reduced, the machining time is saved, the production cost is reduced, the intelligentized degree is high, and practicality is good.