Objective: In order to solve the problem of poor integrity with mechanical coring and get the lantern pulp, and explore the factors affecting the performance of longan coring. Methods: Taking Guangdong 'Chuliang' longan fresh fruit as the research object, the key parts of core removal were designed and the core removal test platform was built. The core removal method with the ejector pin and flexible washer positioning was adopted. The ejector diameter, the rubber washer bore diameter and the ejector speed were chosen as the three main factors,and the stoning success rate, the stoning loss rate and the pulp integrity coefficient were chosen as the evaluation indicators. The single factor and orthogonal experiments were designed. Results: The experiments showed that the ranking of influence was rubber washer aperture ＞ ejector diameter ＞ ejector speed. When the ejector diameter was 7 mm, the rubber washer bore diameter was 14 mm and the ejector speed was 400 mm/min, the best stoning effect was got. Conclusion: It is feasible to obtain longan lantern pulp by the ejector rod mechanical enucleation method positioned with flexible washer and appropriate enucleation operation parameters.