Abstract:Pampus argenteus and Pampus cinereu are two of the most important commercial species of inshore waters in China. The reproductive characteristics of the two species were discussed by means of biological investigation and histological slides analysis with optic microscope. The samples of these two species had been collected continually all year by fishing vessels at sea. The results indicated that the two species had same sex ratio(1∶1) during the spawning season. There was little variation in their gonad and oocyte development. The egg diameter of oocyte at the 5phase was 700-870 μm with one oil globule at 260-400 μm diameter, and the thickness of primary egg membrane was 12-19 μm. They spawn several batchs during one reproductive season. Average fork lengths of female Pampusargenteus and P. cinereu in their reproductive season were 22.5 cm and 29.0 cm, respectively, and the fork length of male Pampus argenteus and P. cinereu in their dominant population was 14.0-17.0 cm and 23.0-25.5 cm, respectively. The reproductive season of Pampus argenteus was from early April to early June and the ovary gonadosomatic index (GSI) went up to its peak from middle of April to middle of May with the maximum 25%. However the reproductive season of P. cinereu was from early June to middle of August and its maximal ovary maximal GSI was 12.6% from late June to late July. In addition, the water temperature in reproductive period for Pampus argenteus and P. cinereu was 18-24℃ and 24-28℃, respectively. The effect of environmental factors on amount of spawning population was also discussed in this paper.