The mother-of-10 was in her 70s and featured in many TV and radio interviews during Michael's 1992 Olympic success when he brought home gold from Barcelona.
The images broadcast around Ireland of Joan and her family at the Carruth household in St Peter's Road, as Michael reached the heights of his dreams, are still vivid to many.
The former welterweight's father Austin 'Aussie' Carruth died in 2011.
Aussie was a legendary boxing coach who steered many boxers to fame and glory – including Michael.
He was a major figure in Irish boxing and helped start the Drimnagh Boxing Club in Dublin.
The couple had been married for more than 50 years and are survived by 29 grandchildren, as well as great-grandchildren.
Michael was part of the Olympic torch procession that carried the London Olympics flame to Dublin last year.