To investigate the parasitic infection on Labeo rohita, one hundred live fishes of different size were collected from different water bodies of Balrampur during July,2016-June,2017. Out of 90, 76 fishes were found infected with fungus, protozoans and metazoan parasites. Among them seven were ectoparasites (Saprolegnia Trichodina, Myxobolus, Chilodonella, Dactylogyrus, Gyrodactylus and Argulus) and three were endoparasites (Trypanosoma, Eucreadium and Camallanus). The infestation showed monthly or seasonal fluctuation, the maximum abundance of parasites was recorded in the month of December and the minimum in July. It was observed that the infection was the maximum in winter and the minimum in the rainy season. Prevalence, intensity and abundance of the infestation were also found to be related to different length group of the hosts, the medium sized fishes were more infested and the larger size fishes were less infested while the smaller size fishes showed medium infestation.