Saptari District(Nepali: सप्तरी जिल्ला), a part of Sagarmatha Zone, is one of the seventy-five districts of Nepal, a landlocked country of South Asia. The district, with Rajbiraj as its district headquarters, covers an area of 1,363 km² and has a population (2001) of 570,282. Saptari is renowned for its agricultural output, and is bordered on the east by the massive Sapt Koshi river.

Significant towns are Rajbiraj, the district centre, Hanumannagar, and Fattepur with the area government "Matsya Palan Kendra" fish farm.

The famous Chhinna Masta Hindu temple and Kankalini temple are also located in Saptari District.