Mersey St. Mary's was an electoral ward of Trafford covering the eastern part of Ashton upon Mersey in Sale, Greater Manchester.
The ward was abolished in 2004, and its area split between the new Ashton upon Mersey and St. Mary's wards. For the ward's entire existence, it elected Conservative councillors on all but one occasion – at its creation in 1973, it elected 1 Liberal councillor alongside 2 Conservative councillors.
| Election | Councillor | Councillor | Councillor | |||
|---|---|---|---|---|---|---|
| 1973 | Brian Clancy (Lib) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1975 | Brian Clancy (Lib) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1976 | Brian Clancy (Lib) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1978 | Ron Moss (Con) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1979 | Ron Moss (Con) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1980 | Ron Moss (Con) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1982 | Stephen Elder (Con) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1983 | Stephen Elder (Con) | Ivor Hurst (Con) | Reginald Bannister (Con) | |||
| 1984 | Stephen Elder (Con) | David Silverman (Con) | Reginald Bannister (Con) | |||
| 1986 | Dora Carter (Con) | David Silverman (Con) | Reginald Bannister (Con) | |||
| Jan 1987 | Dora Carter (Con) | David Silverman (Con) | Stanley Brownhill (Con) | |||
| 1987 | Dora Carter (Con) | David Silverman (Con) | Stanley Brownhill (Con) | |||
| 1988 | Dora Carter (Con) | David Silverman (Con) | Stanley Brownhill (Con) | |||
| 1990 | Dora Carter (Con) | David Silverman (Con) | Bernard Sharp (Con) | |||
| 1991 | Dora Carter (Con) | David Silverman (Con) | Bernard Sharp (Con) | |||
| 1992 | Dora Carter (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 1994 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 1995 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 1996 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 1998 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 1999 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 2000 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 2002 | Brian Rigby (Con) | John Tolhurst (Con) | Bernard Sharp (Con) | |||
| 2003 | Brian Rigby (Con) | John Tolhurst (Con) | John Lamb (Con) | |||