Japanese Encephalitis is a mosquito borne viral infection and is leading cause of childhood encephalitis. Growth of population, paddy farming, pig rearing, lack of surveillance, awareness and vaccination, compromised immune system are the key factors for the transmission of the disease. Although various studies have been conducted on epidemiology of JE. Still the need for further research to have a much clear understanding of the disease and its relation with various factors like demographic profile, age, sex, geographical distribution, seasonal effects, etc. is needed.

        This descriptive study was conducted over collected samples in the Department of Microbiology, PMCH, Patna, Bihar. Confirmation of JE was done by IgM ELISA method. Data so obtained were arranged accordingly in percentage or numbers as required.

       Children of age group 0 to 15 years were more susceptible, rural population was more vulnerable, and post rainy season shows peak for JE infection. Many of the patients discharged with some disability.