James William Dietz (born January 12, 1949) is an American rower and rowing coach.

[2] He competed in single sculls at the 1971 European Rowing Championships (sixth place)[3] and again two years later in 1973 (eleventh).

He made the team for the 1980 Summer Olympics but did not travel to Moscow due to the boycott initiated by the United States.

His squads have produced 69 Atlantic 10 gold medals in 12 separate league championship events, including 13 by his Varsity 8+ boats.

For his efforts, Dietz has been honored as Atlantic 10 Conference Coach of the Year a league-record 10 occasions, including during three of the last four campaigns.