Abstract: In order to study kernel damage mechanism and regularity during peanut shelling process and improve design of peanut sheller, main peanut varieties planted in Liaoning province were taken as example, peanut kernel' shape characteristics, damage characteristic and regularity was studied by micro-electronic tension and compression testing machine and stereo microscope, some relevant mechanical test were carried out under different varieties of peanut kernels, different load-speeds and different compression positions. The results showed that the crushing force to peanut kernel were remarkable when peanut kernels are different varieties and they are compressed under different positions; at the loading rate of 10 mm/min, the average crushing force on right side and lateral side of Silihong were 106.2 N and 96.6 N, correspondingly, Huayu23 were 79.8 N and 58.3 N; Breaking deformation and maximum breaking load-forces were both reduced when load-speed were increased.