Nijgadh (Nepali: निजगढ) is a town and municipality in Bara District in the Narayani Zone of south-eastern Nepal. The existing Nijgadh village was merged with the existing Ratnapuri VDC and Bharatganj Singaul VDC in May 2014.
At the time of the 2011 Nepal Census, Nijgadh had a population of 19,614 persons (9,525 male and 10,089 female) living in 3,982 individual households.
The town has been targeted as a site for an international airport that could handle 15 million passengers and even accommodate the super-jumbo Airbus A380 after the first phase of construction. As of April 2011, a feasibility study of the report was completed. The report stated that the airport would cover 3,000 hectares of land: 2,000 hectares for airport and the remaining 1,000 for the airport city.