Gopalpur Assembly constituency is one of 243 legislative assembly constituencies of the legislative assembly of Bihar. It is a part of the Bhagalpur Lok Sabha constituency along with other assembly constituencies viz Bihpur, Pirpainti, Kahalgaon, Bhagalpur and Nathnagar. The town of Gopalpur, Bihar is part of this constituency.
Gopalpur comprises CD Blocks Gopalpur, Naugachhia, Rangrachowk & Ismailpur.