Abstract:The ripe eggs and spermatozoa of the pearl oyster Pinctada chemnitzi (Philippi)were fertilized in ammoniated seawater. The maximum fertilizing rate was 65%. Thefertilizing rate depends on the maturity of tho genital products. Although by raisingNH4OH in seawater can increase fertilizing rate but it will affect the normal develop-ment and the hatching rate. The concentration of NH4OH in ammoniated seawaterabout 0.14‰ seems suitable.Yeast is not suitable for feeding the straight-hinge stage larvae ofP. chemnitzi.The sperm of P. fucada or a mixture of sperm with Dicrateria zhanjiangensi sp. aremost suitable for the larvae of the stage nd the growth rate is higher than that usesDicrateria zhanjiangensis sp. as food alone. The larvae of the umbo stage are able tofeed with Platymonas sp. and then the growth becomes fast. The growth rates of juvenile mollusk of each food group of yeast, sperm, Dicrateria zhanjiangensis sp. anda mixture of sperm with Dicrateria zhanjiangensis sp. are 0. 03%, 10.22%, 14.73%and 17. 41% respectively.