Abstract:The tiger crab, Orithyia sinica is a commercially important, edible crab which is distributed in the north-west of the Pacific. Experiments were conducted to identify the effect of salinity and temperature on survivorship and food intake of Orithyia sinica. The results showed that, with a quick salinity change, the survival rate of Orithyia sinica was 100% for 8 days at salinity levels 15-40. The crab fed at salinity 10-45 , the mean food intake was ＞1.31g/d. The crab fed well at salinity 20-40 , the mean food intake was ＞3.65g/d. The crab fed best at salinity 30-35 , the mean food intake was ＞5.24g/d. With the gradual salinity change, the survival rate of Orithyia sinica was 100% for 8 days at salinity 15-55. The crab could feed at salinity 5-50. The crab fed best at salinity 25-35, the mean food intake was ＞4.13g/d. With quick temperature change, the survival rate of Orithyia sinica was 100% for 7 days at 10-30℃. The crab fed at 10-35℃, the mean food intake was ＞1.10g/d. The crab fed best at 20-30℃, the mean food intake was ＞8.76g/d. With the gradual temperature change, the survival rate of Orithyia sinica was 100% for 7 days at 0-30℃, and 80% at 35℃. The crab could feed at 10-35℃. The crab fed best at 20-30℃, the mean food intake was ＞12.61g/d. Because, the crab could survive at the salinity 5-55, the appropriate survival salinity was 15-45, the proper salinity for food intake was 25-35, and the optimum salinity for food intake was 30, the Orithyia sinica is living in inshore that suit to live in relatively low salinity seawater. Because, the crab can survive at 0-35℃, can feed at 10-35℃, the proper temperature for intake of food was 20-30℃, and the optimum temperature for intake of food was 25℃. Therefore, the Orithyia sinica is a temperate crab that distributed in the north-west of the Pacific, from the north of South China Sea to the Korean peninsula.