Chainpur is one of the largest villages of Saharsa District in the Indian state of Bihar in North-East India, and is in the Kosi Division.

Chainpur and its surrounding areas are a flat alluvial plain forming part of the Kosi river basin.

Flooding is a major reason for the poor connectivity of the area as bridges tend to get washed away.

potato, cauliflower, brinjal, carrot, radish, lady finger etc., are cultivated in this village.

Every year, a grand mela and wrestling Competition is organised on the occasion of Kali puja in the village.