After playing prep school basketball for a season in Maine at MCI Maine Central Institute, Miller returned to his home state to attend Purdue University, located in West Lafayette, Indiana, where he played under head coach Gene Keady and assistant coaches Bruce Weber and Frank Kendrick.

They beat Rhode Island in overtime, where Brad scored 31 points, grabbed eight rebounds and set a school tournament record with made/attempted free throws, going 15–21 from the line.

Averaging 17.2 points and 8.8 rebounds in his last season at Purdue, he led the Boilermakers to a Sweet Sixteen appearance and a 2nd overall seed in the NCAA Tournament.

After college, because of the NBA lockout, Miller started his career in the Italian Serie A with Bini Viaggi Livorno for three months.

While signing with the Kings, Miller stated, "I wanted to stay with Indiana but my agent said that the money I could make with Sacramento was just too good to pass up and I would never get this kind of contract again."

On November 21, 2003, Miller recorded his first career triple-double with 22 points, 14 rebounds, and 10 assists in a win over the Orlando Magic.

Averaging 14.1 points and 10.3 rebounds in his first season with the Kings, he was voted to back-to-back NBA All-Star Game appearances.

On January 14, 2009, Miller recorded his first 30/20 game with 30 points and a career-high 22 rebounds in a win over the Golden State Warriors.

As a veteran presence on a young team, Miller added depth in the paint with forward/center Joakim Noah to compete in the 2009 NBA Playoffs after a two-year absence of postseason play while with the Kings.

[5] On April 28, Miller received a busted lip by Boston Celtics guard Rajon Rondo, and missed game-decisive free-throws at the end of game 5 of the Eastern Conference First Round.

During game six of the 7-overtime series and after receiving 7 stitches for his lip, he posted a double-double with 23 points and 10 rebounds, shooting 8 for 9 from the floor.

On November 12, 2010, in Miller's first start after coming to the Rockets, he scored 23 points, grabbed 8 rebounds, and gave out 5 assists.

On December 3, 2010, Miller tied his season-high 23 points, going a perfect 7-7 from the field, including 3-3 from downtown, and 6-7 from the foul line.

[13] Shortly after finishing his college career, Brad joined the US national team in the 1998 FIBA World Championship.

[14] With fellow former Purdue standout Jimmy Oliver, Miller led the USA team to the bronze medal.

Miller was selected as a member of the U.S. squad that competed in the 2006 FIBA World Championship, where he played along with fellow NBA players, such as LeBron James, Carmelo Anthony and Dwight Howard.

The Princeton offense run by the Kings both allowed and demanded Miller to be a good passer, and he was typically recognized as one of the best-passing big men in the league.