The invention relates to method of crossbreeding the exotic fresh water crayfish, especially to method of crossbreeding the Luo shi swamp shrimp. The invention introduces the distant Luo shi swamp shrimp sprout A, mating the female parent shrimp and male parent shrimp of the distant Luo shi swamp shrimp sprout A with that of native breed and getting the cross cut B1+ and negative cross B1-; mating the cross cut B1+ and negative cross B1- with the native breed and getting the backcross B2++ of B1+, negative back cross B2+- of B1+, negative back cross B2-- of B1- and back cross B2-+ of B1-; breeding the backcross B2++ of B1+, negative back cross B2+- of B1+, negative back cross B2-- of B1- and back cross B2-+ of B1-. The survival rate and seed-accumulating rate of the four kinks of sprout is all good, the composition of water, coarse ash content, coarse protein, coarse fat content, amino acid and aliphatic acid is higher than that of native obviously by applying the technique in this invention, especially the breed-accumulating rate of the cross B2-+ of B1- is increased to 67.25%, the rate of emergence to 94.56%.