The effects of temperature and salinity on hatching rate of fertilized egg were examined to develop the method for the efficient seed production in fleshy shrimp, Penaeus chinensis. At the temperature ranging from , the hatching rate increased with temperature and the highest hatching rate occurred at . But, with the temperature above , the hatching rate decreased suddenly, and at , the egg did not hatch at all. The hatching rate increased with salinity within the range of and the highest hatching rate occurred at . However, with the salinity above , the rate decreased abruptly, and it was only . The hatching speed of egg was the fastest at . The hatching rate at with the salinity of within 18hrs of the hatching experiment and it attained to within 48hrs of the hatching experiment. At , the hatching rate with the salinity of is 1,2 times higher than that of egg with the salinity of .