The Religious Sisters of Mercy (R.S.M.) are members of a religious institute of Catholic women founded in 1831 in Dublin, Ireland by Catherine McAuley (1778 - 1841). In 2003 the institute had about 10,000 members worldwide, organized into a number of independent congregations.

Sisters of Mercy may refer to:

• Sisters of Mercy, a world-wide Catholic religious order founded by Catherine McAuley.
• Sisters of Mercy of St. Borromeo a religious congregation founded in France
• The Sisters of Mercy, a British rock band
• "Sisters of Mercy", the title of the 39th episode of the TV series Law & Order
• "Sisters of Mercy", a song by Leonard Cohen on the album Songs of Leonard Cohen
• "Sister of Mercy", a song by the Thompson Twins on the album Into the Gap
• "Sisters of Mercy", a song by Phil Lynott's Grand Slam on the album Live 1984