This study was aimed to observe the fecundity of male adult Litopenaeus vannamei during the period of stocking indoor. Shrimp fed with fresh meat of hard clam had higher GSI and spermatophores than those fed artificial diet on the 20th day, but the results reversed on the 40th and 60th days. The number of spermatozoa of the vas deferens was higher on the 40th and 60th day than that on the 20th day. Percentage of normal spermatozoa either in spermatophore or in vas deferens was higher on the group fed with hard clam but the difference did not reach significant level (P > 0.05). The fecundity of shrimp fed with hard clam as unique diet was also investigated on every 10 days’ interval. GSI of white shrimp reached to a maximum on the 10th day, and then decreased to a minimum on the 40th day. The number of spermatozoa of spermatophore or vas deferens increased to a maximum on the 20th day (in the spermatophore, 0.85´106; in the vas deferens, 3.68´106), and then decreased afterward.