Potatoes are easily damaged by extrusion and collision during harvesting, processing and transportation. In this paper, fresh potato samples are cut as a specimen, a Food Texture Analyzer is used to conduct compression tests to simulate extrusion and collision damages, and multiple compression of one sample is used to simulate accumulative damages. The displacement-load relationship of potato specimen is analyzed after being compressed for one or multiple times without being damaged. The plastic deformation characteristics of potato after multiple compression with different loads is studied, and its accumulative damage characteristics are analyzed. The results show that the critical failure point of potatoes will not change even under repeated loads, and there is a bio-yield point of potatoes when the force exceeds the bio-yield point, as well as potato plastic deformation which known as damages. The characteristics of potato accumulative damage show that the damage volume of potato will accumulate with multiple compression. Furthermore, the accumulative damage volume increases greatly when the next compression displacement exceeds the maximum displacement of the potato specimen compressed over, and the accumulative damage volume increases less when the next compression displacement is lower than the maximum displacement of the potato samples compressed over. The above results play a important role in the designing of potato harvesting, processing and transportation equipment.