Gachh Mahadewa is a village in Jokihat tehsil in district of Araria, Bihar, India. As per the data provided by Census of India in 2011, total population of Gachh Mahadewa was 389 which includes 180 males and 209 females. Gachh Mahadewa covers 47 ha area. Pincode of Gachh Mahadewa is 854329.