Katherine Aiken (née Grob; 24 March 1879 - 12 January 1990) was a verified American supercentenarian. She was born as Katherine Grob in Cleveland, Cuyahoga County, Ohio. Her parents were Jacob and Elizabeth Grob. She married Howard Aiken on 12 October 1897. Together, they ran a plumbing business. The couple had one child in total. She was active in the Republican party. She became a widow in 1929.
She died on 12 January 1990, at the age of 110 years, 294 days.