Abstract: In order to intuitively reflect the evolution process of the cracks on the surface of similar material samples and the location and shape of the cracks, sand, cement, gypsum and other materials are used to make similar material samples, and the non-contact strain measurement system is used to observe and study the uniaxial compression state, the whole process of the destruction of samples of similar materials. The test results show that compared with the traditional test method, the digital image correlation technology has obvious advantages. The full-field strain cloud image obtained by this method can better reflect the evolution characteristics of the cracks in the failure process of the similar material samples; the “X”-shaped deformation concentrated zone on the sample surface is taken to measure points, and the strain curve of each measuring point is analyzed by VIC-3D analysis software, and the deformation characteristics of the deformation concentrated zone on the sample surface are obtained; compared with the axial strain rate, the change characteristics of the surface strain rate of the specimen at each stage are obtained.