Justin Kyle Smoak (born December 5, 1986) is an American former professional baseball first baseman. He played in Major League Baseball (MLB) for the Texas Rangers, Seattle Mariners, Toronto Blue Jays, Milwaukee Brewers, and San Francisco Giants and in Nippon Professional Baseball (NPB) for the Yomiuri Giants.

Smoak played baseball for Stratford High School and the University of South Carolina. He was the 11th overall selection in the 2008 MLB draft by the Texas Rangers. He made his MLB debut with the Rangers in 2010, and was traded to the Seattle Mariners that season. He was claimed by the Blue Jays off waivers in 2014, and played for them until 2019. He was an All Star in 2017, and was fifth in the American League that season with 38 home runs.

Smoak graduated from Stratford High School in 2005, after four years of high school baseball. It wasn't until his junior year that scouts began to notice his talent, as they were originally there to scout his teammate and friend, Matt Wieters. He was named by American Baseball Coaches Association, Baseball America, and Collegiate Baseball as a 2005 high school All-American. He was also one of 36 high school players in the nation to play in the 2005 high school All-American baseball game, named South Carolina AAAA Player of the Year in 2004 and 2005, named co-Mr. Baseball for 2005 in South Carolina (alongside Gamecock teammate Reese Havens), made the 2004 and 2005 South Carolina AAAA All-State team, and a member of the 2005 South Carolina AAAA state championship team while with the Stratford Knights. He was initially drafted by the Oakland Athletics as a 16th-round pick in 2005 upon graduation, but instead attended the University of South Carolina.

Smoak went on to play college baseball for the South Carolina Gamecocks for three years. After batting .303 with 17 home runs and 63 RBIs, Smoak earned Freshman All-American honors. He followed up with a .315 batting average, 22 home runs, and 72 RBIs in his sophomore year, good enough to be tabbed as a third-team All-American. For his junior year, Smoak batted .383, with 23 home runs and 72 RBIs. Smoak was a semi-finalist for the Golden Spikes Award in 2007 and 2008. Smoak is South Carolina's all-time home run king with 62, having broken Hank Small's record of 48, which stood for over 30 years. He is also South Carolina's career leader in RBIs and walks.

In the summer of 2006, Smoak played for the Cotuit Kettleers in the Cape Cod Baseball League (CCBL). He led all hitters with 11 home runs, a .565 slugging percentage, and 21 extra-base hits, en route to the MVP award. Smoak is a member of the CCBL Hall of Fame class of 2022.

In the summer of 2007, Smoak was a representative for Team USA. During the 2007 Pan American Games, Smoak struggled, hitting .190 for the tournament. He won a silver medal there, when his team lost to Cuba in the finals. Later, he competed with Team USA again in the 2007 World Port Tournament. However, he didn't fare much better, as he finished with a .208 average, though he did lead the tournament with three doubles. In all, Smoak hit .223 and had a .380 slugging percentage for Team USA over the summer.

In 2009, Smoak again represented his country in the IBAF Baseball World Cup. Smoak hit nine home runs and drove in 22 runs, and was named to the 2009 IBAF World Cup All-Tournament Team along with fellow Team USA players Terry Tiffee and Jon Weber. He was also named the 2009 Baseball World Cup's Most Valuable Player. He won the USA Baseball Richard W. "Dick" Case Player of the Year Award in 2009.

Smoak was the 11th overall selection in the 2008 MLB draft by the Texas Rangers. USA Today opined that "getting Smoak at No. 11 may be the best-value pick of the first round."