Valbuena grew up in Sucre, a municipality in the Venezuelan state of Zulia. He was raised by a single mother named Nelly, who was the president of the local youth baseball league. Valbuena's older brother and several uncles also helped him to learn to play baseball.
Valbuena began his professional career in the Seattle Mariners organization in 2005. He was first promoted to the major leagues on September 1, 2008, from the Mariners' Triple-A team, the Tacoma Rainiers.
On December 10, 2008, he was traded to the Cleveland Indians in a three-team trade that sent Franklin Gutiérrez to Seattle.
Valbuena's first Major League home run came off of Bartolo Colón.
In July 2011, the Indians optioned Valbuena to Triple-A Columbus, to make room for the promotion of rookie second baseman Jason Kipnis.
In August 2011, Valbuena was recalled after Kipnis was put on the disabled list with an oblique injury. He was designated for assignment and removed from the 40-man roster on November 18, 2011. On November 26, 2011, he was traded to the Toronto Blue Jays for cash considerations.
On April 4, 2012, Valbuena was claimed off waivers by the Chicago Cubs after being optioned by the Blue Jays. He was outrighted to the minors on April 7. Valbuena was called up from the Triple-A Iowa Cubs on June 14.
Valbuena played 108 games for Chicago in 2013, hitting .218 with 12 home runs and 37 runs batted in (RBI). The next year, Valbuena's batting average increased to .249 over 149 games and he had 16 home runs and 51 RBI. By June 2014, Fangraphs noted that Valbuena was hitting fastballs well in the lower, outer portions of the strike zone, which had been a weakness for him in previous years.
On January 19, 2015, the Cubs traded Valbuena and Dan Straily to the Houston Astros for Dexter Fowler. At the time of the trade, Valbuena was projected as the Astros starting third baseman for 2015. Valbuena's average dropped to .224 in 2015, but he set a career-high with 25 home runs. With Jed Lowrie coming off the disabled list and Carlos Correa taking over the primary shortstop position, Valbuena was forced to share some of the first base duties along with Chris Carter and utility player Marwin González in order to get some playing time.
At the beginning of the 2016 season, Valbuena was the starting third baseman for the Astros. He began to split playing time between first and third base. With the call up of Astros prospect Alex Bregman, Valbuena has seen more playing time at first base.
On January 24, 2017, Valbuena signed a two-year contract with the Los Angeles Angels.