Mangsebung () is a rural municipality (gaunpalika) out of six rural municipality located in Ilam District of Province No. 1 of Nepal. There are a total of 10 municipalities in Ilam in which 4 are urban and 6 are rural.
According to Ministry of Federal Affairs and Local Development Mangsebung has an area of and the total population of the municipality is 18503 as of Census of Nepal 2011.
Banjho, Ibhang, and Gajurmukhi which previously were all separate Village development committee merged to form this new local level body. Fulfilling the requirement of the new Constitution of Nepal 2015, Ministry of Federal Affairs and Local Development replaced all old VDCs and Municipalities into 753 new local level body (Municipality).
The rural municipality is divided into total 6 wards and the headquarter of this newly formed rural municipality is situated in Ibhang.