AbstractIndian major carps (IMCs) are one of the most economically important as well as edible food fishes all over the world. IMCs are showing different disease problems that cause harm for healthy fishes. The present study was carried out from 12 months of survey study between June 2021 to May 2022 for investigations of different causative fish parasites. In this section, our area of concerning fishes were cyprinidae family fishes the ectoparasites infect them which belong to groups of myxozoan, and protozoan fish parasites that lead to cause severe damage and finally, mass mortality has been observed. In Labeo catla (Hamilton, 1822) showing highest Myxobolus infection was observed in the rainy season (65.55%), and Thelohanellus infection was abundant in winter (65.83%). Another way, L. rohita showed a massive Myxobolus infection rate in January (56.66%), Thelohanellus and Trichodina infections highest in April (63.33% and 53.33%). In this article, the prevalence of parasitic studies has been dealt with. As per seasonal diversity, host age, size of the hosts and sex-wise prevalence of parasitic infection over the fish sectors. Here, parasitic infections were shown at different time scales which are stated in this research article. As per the sex wise study, the highest infection was observed in females as compared to male fishes. The large sized fishes were highly prone to parasitic diseases as subjected to small young fishes.