Udayapur 1 is one of two parliamentary constituencies of Udayapur District in Nepal.

This constituency came into existence on the Constituency Delimitation Commission (CDC) report submitted on 31 August 2017.

[1] Udayapur 1 incorporates Belaka Municipality, Chaudandhigadhi Municipality and Triyuga Municipality.

It encompasses the following Province No.

1 Provincial Assembly segment