| Magarthana | |
| Other Name: | Magarthan |
| Native Name: | Jai baba mangalnath |
| Nickname: | Magarthana |
| Settlement Type: | Village Development Committee |
| Pushpin Label Position: | bottom |
| Pushpin Mapsize: | 360 |
| Pushpin Map Caption: | Location in Nepal |
| Subdivision Type: | Country |
| Subdivision Name: |  Nepal |
| Subdivision Type1: | Zone |
| Subdivision Name1: | Janakpur Zone |
| Subdivision Type2: | District |
| Subdivision Name2: | Mahottari District |
| Population As Of: | 1991 |
| Population Total: | 9890 |
| Population Density Km2: | auto |
| Population Blank1 Title: | Ethnicities |
| Utc Offset: | +5:45 |
Sundarpur is a Village Development Committee in Mahottari District in the Janakpur Zone of south-eastern Nepal. At the time of the 1991 Nepal census it had a population of 8971 people residing in 1766 individual households.