This study aimed to investigate the concentrations of two heavy metals, lead and cadmium, in the water of Zayandehroud River which is surrounded by Zarinshahr rice farms. Water was sampled from a depth of 30 cm during June, July and August 2015, i.e. during the process of planting, growing and after harvesting, in three stations. Water was collected from three points; 20m before the farms, beside the farms and 100m after the farms. Three water samples and one trout fish (Salmo trutta) sample were collected each month and the concentrations of lead and cadmium were measured in the kidney, liver and gills of trout fish. The results showed that the amounts of lead and cadmiumin in the water were less and more than standard levels for these metals, respectively. The average concentrations of cadmium in the water were 15.81, 11.25, 8.92 mg/L during June, July and August, respectively. It is evident that the amount of cadmium in water was significantly higher in June during the planting phase and use of fertilizers and pesticides was more than the other months (p < /em>£0.01). There was a correlation in cadmium and lead concentrations between water and fish organs (kidney, liver and gill).