Abstract: The preservation effects of Tremella fuciformis polysaccharides on Penaeus vannamei were studied in the present study. P. vannamei was treated with different concentrations（0.2%, 0.4%, 0.6%, 0.8%, 1.0%） of T. fuciformis polysaccharides and then stored at 4 ℃ for 8 days, then the sensory and melanosis evaluations were carried out every two days using 1% sodium sulfite（CK1） and distilled water（CK2） treatments as controls, and the p H, total volatile basic nitrogen（TVB-N）, thiobarbituric acid（TBA） values, color differences, water holding capacities, and total bacterial counts were also measured. Results showed that T. fuciformis polysaccharides could inhibit the deterioration of sensory qualities and melanosis of P. vannamei, delay the increases of pH, TVB-N and TBA values, reduce the water loss and inhibit the bacterial growth. The concentration of 0.6% T. fuciformis polysaccharides exhibited the superior preservation effects.