The invention discloses a method for detecting workpiece defects by depth continuous change based artificial grooving. The method comprises the following specific steps: firstly selecting a comparisontest block, processing out artificial defects for simulating depth continuous changes of a defect position on a practical workpiece on the comparison test block, putting a probe on the artificial defects to practically mark, recording amplitude values of the artificial defects and positions, on a display screen, of the artificial defects as standards, detecting the practical workpiece, comparingwith response of the artificial defects on the comparison test block, judging that the part has defects if response similar with the artificial defects on the comparison test block exists, and the position is matched, otherwise, judging that the part does not have defects, and moving the probe to continuously detect all detected surfaces until all areas on the practical workpiece are detected. Themethod disclosed by the invention adopts artificial defects with depth continuous changes to solve the problem that all defects on the workpiece cannot be comprehensively evaluated by artificial defects specified by the existing standards.