McKay, Mary Ann
- Township: Embro & West Zorra
- Rank: Nursing Sister
- Date of birth: 1880
- Where born: Harrington West, West Zorra Township, Oxford County, Ontario, Canada
- Wars Served: World War I
- Country enlisted with: Canada
Mary Ann McKay was born 1880, daughter of John R. and Harriet (Martin) McKay of Harrington West (963668). She was a nurse in the First World War.