Budenholzer's first head coaching assignment will have to wait until the end of the NBA Finals, however, as the Spurs have advanced to the league's championship round.
Budenholzer, 43, has been the lead assistant to San Antonio Coach Gregg Popovich for the last six seasons and has been on the team's coaching staff for 17 of the last 19 seasons, including NBA title runs in 1999 and 2007.
"We are thrilled to have Mike as the next coach of the Atlanta Hawks," said Hawks General Manager Danny Ferry. "He has an incredible basketball acumen and has a keen awareness of the league and what it takes to be successful. His experience and four championships over the last 17 years provide a tremendous foundation for his leadership of our team."
Budenholzer replaces Larry Drew, who resigned after last season's 44-38 campaign to seek other coaching opportunities. Atlanta was 128-102 under Drew, going to the playoffs three consecutive seasons.
"I have been extremely fortunate to be a part of the San Antonio Spurs organization for the last 19 years," Budenholzer said. "I knew it would have to be a tremendous situation for me to leave and clearly coming to Atlanta as the head coach of the Hawks is perfect for me."