| Sierpc County | |
| Native Name: | Powiat sierpecki |
| Settlement Type: | County |
| Total Type: | Total |
| Image Map1: | POL powiat sierpecki map.svg |
| Map Caption1: | Division into gminas |
| Subdivision Type: | Country |
| Subdivision Type1: | Voivodeship |
| Subdivision Name1: | Masovian |
| Area Total Km2: | 852.89 |
| Population Total: | 52077 |
| Population As Of: | 2019 |
| Population Density Km2: | auto |
| Population Urban: | 17994 |
| Population Blank1 Title: | Rural |
| Population Blank1: | 34083 |
| Coor Pinpoint: | Sierpc |
| Coordinates: | 52.8833°N 59°W |
| Seat: | Sierpc |
| Parts Type: | Gminas |
| Parts: | Total 7 (incl. 1 urban) |
| P1: | Sierpc |
| P2: | Gmina Gozdowo |
| P3: | Gmina Mochowo |
| P4: | Gmina Rościszewo |
| P5: | Gmina Sierpc |
| P6: | Gmina Szczutowo |
| P7: | Gmina Zawidz |
| Blank Name: | Car plates |
| Blank Info: | WSE |
| Website: | http://www.powiat.sierpc.pl |
Sierpc County (Polish: powiat sierpecki) is a unit of territorial administration and local government (powiat) in Masovian Voivodeship, east-central Poland. It came into being on 1 January 1999 as a result of the Polish local government reforms passed in 1998. Its administrative seat and only town is Sierpc, which lies 117km (73miles) north-west of Warsaw.
The county covers an area of 852.89km2. As of 2019 its total population is 52,077, out of which the population of Sierpc is 17,994, and the rural population is 34,083.[1]
Sierpc County is bordered by Żuromin County to the north-east, Płońsk County to the east, Płock County to the south, Lipno County to the west and Rypin County to the north-west.
The county is subdivided into seven gminas (one urban and six rural). These are listed in the following table, in descending order of population.
| Gmina | Type | Area (km2) | Population (2019) | Seat |
| Sierpc | urban | 18.6 | 17,994 | |
| Gmina Sierpc | rural | 150.2 | 7,024 | Sierpc * |
| Gmina Zawidz | rural | 186.1 | 6,608 | Zawidz |
| Gmina Mochowo | rural | 143.6 | 6,037 | Mochowo |
| Gmina Gozdowo | rural | 126.7 | 5,946 | Gozdowo |
| Gmina Szczutowo | rural | 112.6 | 4,327 | Szczutowo |
| Gmina Rościszewo | rural | 115.1 | 4,141 | Rościszewo |
| ||||