The spawning periodicity of silver pomfret, Pampus argenteus, was investigated in 627 specimens (137 female and 490 male) collected monthly by trawl net from the Northwest the Persian Gulf for a one year period (March 2004 to February 2005). Seven maturity stages were recognized by Kesteven scale. The length at first maturity (LM50) was calculated as 192 mm in combined sex. The overall sex ratio (female: male) was 1:3. Fluctuations in the Gonadosomatic Index (GSI) values and percentage of mature specimens suggested prolonged spawning season from May to October. There were two spawning peaks, the first one between May and July and the second in October. It is concluded that Iranian waters (in Khuzestan province)are the main spawning and nursery grounds for silver pomfret in the Persian Gulf.