Theodore "Ted" Roosevelt Lilly III (born January 4, 1976, in Lomita, California), is a Major League Baseball starting pitcher for the Chicago Cubs. He bats and throws left-handed. Lilly attended Yosemite High School in Oakhurst, California, and Fresno City College.

Lilly broke into the majors with the Montreal Expos in 1999, pitching in only nine games that year before being traded to the New York Yankees as part of a trade involving Hideki Irabu. Lilly played for more than two years for the Yankees before being dealt to the Oakland Athletics in a three team deal that included pitchers Jeff Weaver heading to New York and Jeremy Bonderman going to the Detroit Tigers. Lilly was in the starting rotation for Oakland, and pitched in the American League Division Series in both 2002 and 2003.

Lilly was traded from the Athletics to the Blue Jays for Bobby Kielty. He made the American League All-Star team in 2004 as the Jays' lone representative that year.