Walker attended University High School in Spokane, Washington and competed in football and track and field In track, Walker was coached by Regional Hulbert and won All-Greater Spokane League honors following his senior season. Walker graduated from University High School in 1999 with a 3.89 Grade Point Average.
Two weeks later in Rieti he set a new personal best of 5.96. In July 2006, at Jockgrim, Germany, Brad Walker, cleared 6 meters, the best performance of the year, in a pole vault competition. On 8 June 2008 Walker jumped in Eugene to a new personal and American record with 6.04.
Walker qualified for the 2008 Olympics, but failed to clear a height in the preliminary rounds.
At the 2012 Summer Olympics, Walker reached the final but finished 12th with a 5.50m vault.
He is the American recordholder and was the 2007 World Champion in the event. In track, Walker was coached by Regional Hulbert and won All-Greater Spokane League honors following his senior season. While there, he became National Collegiate Athletic Association indoor pole vault champion twice and four-time National Collegiate Athletic Association All-American under Coach Pat Licari. In 2005 he became both indoor and outdoor National Champion. Perhaps not among the favorites in the 2005 World Championships, Walker nonetheless won the silver medal with 5.75. In 2006 he won the World Indoor Championships in Moscow with a jump of 5.80meters. He won the gold in the world championships on 1 September 2007. Walker retained his United States championship title in 2009, even though his status as reigning World Champion gave him a bye into the 2009 World Championships in Athletics.
