Aseries of experments have been conducted in determining the influences of the totalsalinity, chemical ingredients, water temperature, dissolved oxygen, and food in theartificial sea water, to the copulation, breeding, hatching, and the development of thezoeal larvae of the woolly-handed crab. The result of the experiments manifests that when the optimum total salinify forspawnmg of the crab is 10‰ to 17‰. and the content of calcium is between 144 mg/L to335 mg/l, the zoeal larvae may develop to megalop stage and within this range there is alendency that the rate of survival is increased by the raise of the caleium content. Thepreferable conlents of Mg, K, and Fe are 461 mg/L--935 mg/L, 200 mg/L--400 mg/Land 0. 02 mg/L--0. 05 mg/L respectively. The content of Cu is very slight and negligi- ble. The changes of the water temperature influence greatly to the hatching of the eggs,and the development of the zoeal larvae. The optimum water temperature for the breedingof the crab is above 14℃, and the hatching of the eggs demands 13--27 days at thewater temperture of 21.1--26.9℃. The optimum temperature for the development ofzoeal larvae is slightly higher than that of the hatahing. The tolerant ability of the zoeal larvae in lacking of oxygen is cmparatively muchlower than that of fishes, when the dissolved oxygen is at 2 mg/L, it would cause a largequantity of zoeal larvae to die, and if further reduced to 1. 4 mg/L, Then death occursinstantly. The optimum content of the dissolved oxygen for normal development of thezoeal larvao is above 4 mg/L. The ideal food in cultivating the zoeal larvae of the woolly-handed crab is thenauplius larvae of the brine shrimps.