Abstract: The mechanical properties of fresh longan was determined in this paper. The results of compression tests showed that the anti-extrusion capacity of fresh longan had good consistency in different directions, and it can be simplified as shell sphere, which was isotropy and uniform thickness. The analysis results based on thin shell theory indicated that using a pair normal concentrated force were benefical to equable cracking of the hulls of longan. During the tensile test on hulls, we found that the bonding force of longan fruit along longitudinal and transversal were all bigger than the pedicel. So one can see inference, the hulls of fresh longan can be peelled off by using roller friction, which provides vital basis for designing of the denucleating and shucking machine.