Heavy metal contamination of aquatic ecosystems due to industrialization and anthropogenic activities has become a serious global issue. Toxic effects of these heavy metals are posing a major threat to the aquatic organisms especially fish. Fishes exposed to lead (Pb), exhibit a wide-range of effects including muscular and neurological degeneration and destruction, growth inhibition, mortality, reproductive problems, and paralysis. Many fish species are used as food source by man. Bio magnification of these metals makes them hazardous for humans. Objective: To evaluate the acute toxicity (96-hr LC50 and lethal concentrations) of Pb in Labeo rohita and the effect of various sub-lethal doses of Pb on different organs (Gills, Liver, and Muscles) of fish. Methods: Live fish samples (150) were shifted from hatchery to laboratory. To measure metal (Pb), accumulation in fish body inductively coupled Plasma mass spectrometry (ICP-MS) was performed. Results: Acute toxicity (96-hr LC50) of Pb was observed as 52.20 mg/l, while Pb accumulation was noted more in gills as compared to liver and muscles. Conclusions: This study will provide baseline information for the control of aquatic pollution and conservation of aquatic organisms