With micro-arithmometer, HITACHI 7170A and BECKMAN CX-3, the number of red blood cell(RBC) and the contents of blood sugar(BG) and mineral-element in blood serum of Rainbow trout were determined at three different wa- ter temperature 14 ℃, 19 ℃ and 23 ℃ The results showed that the number of RBC of Rainbow trout reduced rapidly with the rising of water temperature from 14 ℃ to 23 ℃ ; the contents of BG in blood serum of Rainbow trout increased at water temperature 19 ℃, and reduced at 23℃ ; the contents of Cu of Rainbow trout increase...