Mary Kelly
Mary Kelly may refer to:
- Mary Jane Kelly (1863–1888), widely believed to be the fifth and final victim of Jack the Ripper
 - Mary Kelly (writer) (1927–2017), Scottish writer
 - Mary Kelly (artist) (born 1941), American artist and writer
 - Mary Kelly (gymnast) (1907–1986), British Olympic gymnast
 - Mary Kelly (born 1985), Australian handball player
 - Mary Kelly (journalist), (1926-2005?), American journalist
 - Mary Kelly (politician) (born 1952), Irish Labour Party politician, Member of the 20th Seanad
 - Mary Beth Kelly, justice on the Michigan Supreme Court
 - Mary Eva Kelly (1826–1910), Irish poet and writer
 - Mary Louise Kelly (born 1971), National Public Radio's senior Pentagon correspondent
 - Mary Kelly (playwright) (1888–1951), British playwright, pageant maker and founder of the Village Drama Society
 - Mary Jane Kelly (band), an Australian hardcore band