Koiri Bigha is a village in Belaganj tehsil in district of Gaya, Bihar, India. As per the data provided by Census of India in 2011, total population of Koiri Bigha was 1,884 which includes 1,013 males and 871 females. Koiri Bigha covers 137 ha area. Pincode of Koiri Bigha is 804403.