| John Joseph Cowan | |
| Birth Date: | 1957 7, df=yes |
| Birth Place: | Penticton, British Columbia, Canada |
| Allegiance: | Canada Australia |
| Branch: | Royal Canadian Navy (1976–96) Royal Australian Navy (1996–) |
| Serviceyears: | 1976 - present |
| Rank: | Captain |
| Commands: | STS Young Endeavour |
| Battles: | International Force for East Timor Operation Sharp Guard |
| Awards: | Conspicuous Service Cross[1] Canadian Forces' Decoration |
Captain John Joseph Cowan CSC, CD (born 23 July 1957) is a Royal Australian Navy (RAN) officer. Cowan originally joined the Royal Canadian Navy (RCN) in 1976 as an ordinary seaman boatswain, eventually being commissioned as an officer in 1988, but transferred to the RAN in 1996. He was the commissioning Commanding Officer of (2011–12).
Cowan was born on 23 July 1957 in Penticton, British Columbia. He joined the Navy League Cadet Corps in his youth and, at age 13, transferred to the Royal Canadian Sea Cadets (RCSC). During his time in the RCSC he spent time onboard CCGS Quadra and later HMC Ship's Terra Nova and Yukon.
John joined the Royal Canadian Navy as an ordinary seaman boatswain in 1976. He is qualified as a surface warfare specialist. He was deployed as part of the Canadian response and support to Operation Sharp Guard for the blockade of the former Yugoslavia. He qualified as a navigator during his seaman officer training course.
He spent the majority of his career as sea serving mainly with the Maritime Forces Pacific. He retired from the Royal Canadian Navy on 7 July 1996 after 13 years service.
John joined the Royal Australian Navy on 8 July 1996, retaining his commission and qualification as a ships navigator. He served as the navigator onboard HMA Ship's Brisbane and Tobruk.
John commanded from December 2008 until May 2010 and took command of for its commissioning for April 2011 until December 2012.