The aim of this study was to find the best location for establishment of rainbow trout culture and hatcheries farms on Zayanderood’s river region in Charmahal and Bakhtiyari province. This survey carried out over ten station along Zayanderood’s river. The result of physical and chemical analysis showd that the annual average of air temperature varied from 9.5oC - 10oC where the pH annual average value were between 7.5 and 8.8. the dissolve oxygen concentration in stations except in rainbow trout farm effluent were above 10 mg/l. the other chemical , pollutant as well as pesticides levels were under the limiting concentration for rainbow trout culture and Hatcheries activity. The plankton survey showed that the Bacillurophyta were the dominant group of phytoplankton where protozoa constituted the most abundant group of zooplankton the Benthic organisms sensitive to pollutant in particular Epirus were dominant group in all stations. In regard to fishes presence in river, five species of Ciprinidae, one species from Balitoridae and one species from salmonidae families were identified. The capacity for development of rainbow trout culture for tow phase period in Zayanderood’s river region with respect to self purification potential (self purification potential were determined from the oxidation of the effluent of the only active trout farm of the river region), minimum of 10 L/s water requirement for production of trout in concrete canal and pond system and 1 L/S water need for production in semi circular closed system were estimated to be 5202 metric tons
