| Official Name: | Mechanicsville, Connecticut |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Connecticut#USA |
| Pushpin Label: | Mechanicsville |
| Coordinates: | 41.9411°N -71.8936°W |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Name1: | Connecticut |
| Subdivision Type2: | County |
| Subdivision Name2: | Windham |
| Subdivision Type3: | Town |
| Subdivision Name3: | Thompson |
| Area Footnotes: | [1] |
| Area Total Km2: | 2.16 |
| Area Land Km2: | 2.16 |
| Area Water Km2: | 0.0 |
| Population As Of: | 2020 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 310 |
| Postal Code Type: | ZIP Codes |
| Postal Code: | 06277 (Thompson) 06255 (North Grosvenordale) |
| Area Code: | 860/959 |
| Blank Name: | FIPS code |
| Blank Info: | 09-46240 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2805993 |
Mechanicsville is an unincorporated community and census-designated place (CDP) in the southern part of the town of Thompson in Windham County, Connecticut, United States. It is bordered to the north by North Grosvenordale and to the south by Putnam. Connecticut Route 12 (Riverside Drive) runs the length of the community, along the east side of the French River.
Mechanicsville was first listed as a CDP prior to the 2020 census.
A portion of the Air Line State Park Trail passes through Mechanicsville, along with the Providence and Worcester Railroad.