Ian Kenneth Stewart (born April 5, 1985) is an American former professional baseball third baseman.

In 2004, Stewart continued to progress in Low-A with the Asheville Tourists in the South Atlantic League with a .398 OBP and .594 SLG.

However, Stewart rebounded later in the season and finished with a respectable .353 OBP and .497 SLG, although he showed a worrisome tendency to strike out.

Stewart re-established himself as a power-hitting prospect, and the Rockies assigned him to the Tulsa Drillers of the Double-A Texas League.

When he returned, Stewart improved noticeably and finished the season with a .351 on-base percentage and a .452 slugging average.

Stewart had his contract purchased to the 40-man roster on August 11, 2007, when Jeff Baker was placed on the disabled list.

Stewart hit his first major league home run, a grand slam on August 21, 2007, against Tony Armas Jr. of the Pittsburgh Pirates, making him only the second Rockie ever to hit a grand slam as his first major league home run.

Stewart struggled early, striking out 28 times in his first 55 at-bats, and was sent down to the Triple-A Colorado Springs Sky Sox to regain his hitting stroke.

On December 8, 2011, Stewart was traded from the Colorado Rockies along with Casey Weathers to the Chicago Cubs in exchange for Tyler Colvin and DJ LeMahieu.

[9] On July 5, 2013, he signed a minor league contract with the Los Angeles Dodgers, who assigned him to the Triple-A Albuquerque Isotopes.