The invention belongs to nondestructive testing technology, and relates to a method for manufacturing a surface crack sample for a nondestructive testing sensitivity test. The method adopts a fatigue loading mode to manufacture a crack defect, and the operation is simple; the manufactured fatigue crack defect has small dimensions and belongs to typical crack defect. Therefore, the manufactured fatigue crack defect has excellent representativeness for natural crack defects. The method can successfully acquire crack samples with dimensions of natural cracks; and dimensions and shapes of the samples and directions and positions of the crack defects can meet most test requirements. The manufacturing process is easily controlled, which is particularly applicable to adjustment and experimental verification for circumferential magnetization detection sensitivity in magnetic particle testing, and the method can be applied to testing research of detecting sensitivity of the surface cracks in three nondestructive testing specialities, namely ultrasound, vortex and penetration.