This research was conducted the effect of environmental parameters on copepods which are edible food for fish larvae in Chabahar Bay. This research was carried out in 4 seasons, summer 2007, fall 2007, winter 2007 and spring 2008. Copepods were collected at 5 stations via a 100µ mesh by vertical plankton tows. 7 of copepods genera were identified as the most economically important genera due to valuable food. Data showed that environmental parameters have an important effect on the abundance of copepods in which some genera increased or decreased during the year. Abundance of Pseudodiaptomus, Temora and Centropages showed negative correlation with temperature but positive correlation with oxygen dissolved. It may explain why these genera had the highest abundance in winter. Positive relationship between abundance of Oithona and chlorophyll-a showed this genus increases with the increase of phytoplankton. There was no significant relationship between abundance of other genera and environmental parameters