| Honorific-Prefix: | Cllr |
| Mary Callaghan | |
| Office: | Dublin City Councillor |
| Term Start: | 24 May 2019 |
| Constituency: | Ballymun–Finglas |
| Birth Place: | Dublin, Ireland |
| Party: | Social Democrats |
| Alma Mater: | University College Dublin Dorset College |
Mary Callaghan is an Irish Social Democrats politician who has represented Ballymun-Finglas on Dublin City Council since 2019. She served as Deputy Lord Mayor of Dublin to then Lord Mayor Hazel Chu from 2020 to 2021. She was elected Deputy Mayor with a 43 to 9 margin, marking the third time in history that the top two positions in Dublin have both been held by women.[1] [2]