Abstract:Chill tolerance of nauplii of Anemia spp. put into freezer at -30℃ for 30 minutes with and without the addition of glucose, sucrose and glycerol at various concentrations was determined. The average liquid cooling rate was 3-5℃ /min, and the average solid cooling rate was 1-1. 3℃/min. All of the control without the addition of the cryoprotective agent died, the addition of the cryoprotective agent enhances the cooling tolerance of nauplii, and the survival varied according to the kind of cryoprotective agent,concentration and balance time, the highest survival of nauplii reached 86. 4% in 20% glycerol when frozen to -30℃for 9-10 minutes. Chill tolerance of zoea of Eriocheir japonicus hepuensis at -25℃was also studied with 20% glycerol,DMSO and methanol. The average liquid cooling rate was 3-4℃ /min, the average solid cooling rate was 0. 3-0. 5℃ /min. All of the control died when frozen to -23℃, the best rsult was 75. 3% survived in 20% methanol when frozen to -24℃. Besides, the significance of these results for the development of cryogenic larval banking techniques was discussed.