Abstract: We study the effects of different temperature (14 ℃, 17 ℃, 20 ℃, 23 ℃, 26 ℃) and salinity (5, 10, 15, 20, 25, 30,35) on the growth and biochemical constituents of Gracilaria chouae. Results indicate that the appropriate temperature for its growth is 14~26 ℃ and optimum is 17~20 ℃. Under 17~20 ℃, G.chouae obtains maximal relative growth rate. But when the temperature is higher than 20 ℃, the growth of G.chouae is inhibited. In addition, its tolerance to low temperature is better than that of high temperature in terms of growth performance, photosynthetic pigments and antioxidant enzymes. The appropriate salinity for its growth is 20~35 and optimum is 30. Under the salinity of 30, G.chouae obtains maximal relative growth rate. Its growth is inhibited when salinity is below 20. G.chouae treated with high salinity has better growth performance, photosynthetic pigment and antioxidant enzymes than that with low salinity.