Abstract: We studied the influence of 3 factors including alkali concentration, soaking time and temperature on gel strength(GS) and yield of Eucheuma carrgeenan by response surface methodology (RSM).On the basis of single-factor investigation, Box-Benhnken central composite experiments were carried out to build the quadratic regression models for GS and yield with the above 3 factors, and the alkali processing technology was optimized by response surface analysis. The optimizing process parameters are: alkali concentration 250 g·L^-1 , soaking time 3.5 d, soaking temperature 25 ℃.Under the optimal processing condition, the GS and yield of carrgeenan were 721 g·cm^-2 (under concentration of 10 g·L^-1) and 35.17%, respectively.