According to Official Guinness Records,
The oldest living mule is Joe (b. 1971), aged 44 years 112 days as of 9 July 2015. Joe lives with his owner, Bert Reissig (USA) in Colorado Springs, Colorado, USA.Bert also owned Joe's sister Josephine.
For a complete list of 2015 records, please visit 2015 Guinness Records in United States.