Multi-Chain Spheroidal Structure Universe Algorithm(MCSSUA) is proposed in order to improve the quality of tomato image surface defect segmentation. Firstly, multi chain spheroidal universe structure topology is established, and the universe can only communicate with the three universes around itself to maintain the balance of the universe. Secondly, the optimal threshold is adopted to segment the tomato defect image, and a separate element is taken as the stop condition for ending the image segmentation. Finally, the flow of the proposed algorithm is given. The simulation shows that the multi-chain spheroidal structure universe algorithm can segment the tomato image surface defect with clear results, and higher correct segmentation rate of various defects than other algorithms.