Ondolajar is a village in Dalgaon tehsil in district of Darrang, Assam, India. As per the data provided by Census of India in 2011, total population of Ondolajar was 3,929 which includes 2,011 males and 1,918 females. Ondolajar covers 263.8 ha area. Pincode of Ondolajar is N/A.