Hu was signed by the Dodgers on January 31, 2003, and began his professional career with the rookie league Ogden Raptors in 2003. He split 2004 between the Columbus Catfish in A ball and the Vero Beach Dodgers in High-A ball. In 2005, he played the whole season at Vero Beach and hit .313 with 23 stolen bases.
In 2006, he played for the Double-A Jacksonville Suns. Hu played in the All-Star Futures Game during the All-Star break in both 2006 and 2007. He won the MVP award for his performance in the 2007 game.
He was promoted to Triple-A Las Vegas on July 12, 2007, and made his major league debut on September 1, 2007, against the San Diego Padres. In his second MLB at bat, Hu hit a solo home run on September 11, 2007, against the Padres, becoming the first position player born in Taiwan to hit a home run in MLB. (Hu's teammate, pitcher Hong-Chih Kuo, had become the first Taiwanese-born player to hit a home run in MLB earlier in 2007). On September 25, Hu hit a two-run homer and became the first Taiwanese-born player to hit two home runs. Hu spent most of 2009 in AAA with the Albuquerque Isotopes and appeared in only five games with the Dodgers after a September callup.
In 2010, he again spent most of the year with the Isotopes. He appeared in 14 games with the Dodgers in 2010 and got 3 hits in 23 at-bats.
After playing for the Adelaide Bite of the Australian Baseball League and starting shortstop for the World All-Stars at the 2011 Australian Baseball League All-Star Game, Hu signed a minor league contract with the Cleveland Indians in January, 2012. He was released on March 28, 2012 and signed to a minor league deal with the Philadelphia Phillies, however his contract was voided the next day after he failed a physical. He then signed with the Southern Maryland Blue Crabs for the 2012 season.
In 2013, he signed with EDA Rhinos of the Chinese Professional Baseball League.