Bagaha Assembly constituency is an assembly constituency in Paschim Champaran district in the Indian state of Bihar.

Bagaha Assembly constituency is composed of the following: Bagaha community development block including Bagaha nagar parishad; and Bairagi, Sonbarsha, Vairati Bariarwa, Kharhat Tribhauni, Chamawalia and Paikwalia Maryadpur of Sidhaw CD Block.

[2] Bagaha Assembly constituency is part of 1.

Valmiki Nagar (Lok Sabha constituency).

[2] It was earlier part of Bagaha (Lok Sabha constituency).