Aim of the present study was to examine the acute and chronic exposure of pesticide, chlorpyrifos (CPF) to the fresh water fish Labeo rohita. During acute exposure, fish were exposed to different concentrations of CPF ranging from 0, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04 and 0.05 mg/L for 96 hrs in glass aquaria. The 96 hrs LC50 value of CPF for Labeo rohita was found to be 0.01 mg/L. During chronic exposure fish were subjected to 1/3rd, 1/5th, 1/7th and 1/9th of LC50 for 30 days. At the end of the trials, tissues from various organs like intestine, liver and kidney were collected and sections were examined under digital microscope. Pronounced histological changes like necrosis, infiltration, atrophy, shrinkage and degeneration of intestine was observed for different CPF concentrations. Kidney sections of Labeo rohita under different CPF concentrations exhibited nuclear hypertrophy, vacuolar degeneration of glomeruli, and occlusion of tubular lumen, cloudy swelling degeneration and hyaline droplets degeneration. In the liver tissue prominent histological changes observed including hepatic cell degeneration, nuclear hypertrophy, bile stagnation, irregular shaped cells, degeneration in the liver parenchymal cells, nuclear and cytoplasmic degeneration. Therefore, we here conclude that Chlorpyrifos adversely affects the major organs of Labeo rohita (Rohu).