| Martonvásár District | |
| Native Name: | Martonvásári járás |
| Native Name Lang: | hu |
| Settlement Type: | Districts of Hungary |
| Image Blank Emblem: | Coa Hungary Town Martonvásár.svg |
| Blank Emblem Type: | Coat of arms |
| Subdivision Type: | Country |
| Subdivision Type1: | County |
| Subdivision Name1: | Fejér |
| Seat Type: | District seat |
| Seat: | Martonvásár |
| Area Total Km2: | 277.13 |
| Area Rank: | 8th in Fejér |
| Population As Of: | 2011 census |
| Population Total: | 28,040 |
| Population Rank: | 7th in Fejér |
| Population Density Km2: | 101 |
Martonvásár (hu|Martonvásári járás) is a district in eastern part of Fejér County. Martonvásár is also the name of the town where the district seat is found. The district is located in the Central Transdanubia Statistical Region.
Martonvásár District borders with Bicske District to the north, Érd District and Ráckeve District (Pest County) to the east, Dunaújváros District to the south, Gárdony District to the west. The number of the inhabited places in Martonvásár District is 8.
The district has 2 towns and 6 villages.(ordered by population, as of 1 January 2012)[1] The bolded municipalities are cities.