Janaki Mandir is a Hindu temple in Janakpurdham, Nepal, dedicated to the Hindu goddess Sita. It is an example of Koiri Hindu architecture. Fully built in bright white and constructed in an area of 1,480 square metres in the Mithila Kingdom, it is a three-storied structure made entirely of stone and marble.

Janakpurdham or Janakpur is a sub-metropolitan city in Dhanusha district, Madhesh Province, Nepal. The city is a hub for religious and cultural tourism. A headquarter of Dhanusha district, Janakpur is also the capital for Madhesh Province.