An attempt has been done to explore the hematological variation in healthy and saprolegnia infected minor carp, Bangana dero. Hematological parameters i.e total erythrocyte count (TEC), total leukocyte count (TLC), hemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were examined in healthy and infected fish of wild and cultured stock. Except TLC, which significantly increased in the infected fish, all parameters decreased in response to infection in wild as well as cultured stock. Decreases in Hb, TEC were significant, indicating that saprolegniosis causes anemia and immunosuppression. Wild stock also has non significant slightly higher values of blood indices except the TLC, showed better health and immunity of wild stock over the cultured stock. The values and trend of the examined parameters are indicators of mycosis in fish and would be used as tool for diagnosis of fungal infected fish.