The senior guard was the only unanimous selection to the 2016-17 AP All-America team Tuesday, receiving all first-team votes from the same 65-member national media panel that selects the weekly AP Top 25.
"I love the kid and I think he knows how I feel about him, but I've never been more proud -- not that he's won a postseason award, but [that] he's done everything that he's supposed to do," Kansas coach Bill Self said. "He's been a great teammate, he's been tough as nails, he's worked his butt off, he's loved by everyone in the academic departments, graduated, and to see him reap these benefits after putting in so much time is an unbelievable honor."
The rest of the All-America team includes guards Josh Hart of Villanova and Lonzo Ball of UCLA, and forwards Caleb Swanigan of Purdue and Justin Jackson of North Carolina. Votes were based on the regular season and conference tournaments.
Mason averaged 20.8 points, 5.1 assists and 4.1 rebounds while shooting 48.7 percent from 3-point range before the start of the NCAA tournament.
"My goals were always just to be successful as a team, do whatever I can do to make sure we're successful and really change it at the defensive end and get after it," Mason said. "Yeah, that's pretty cool to see my name alongside those great KU players, it means a lot to me, but nothing would be possible without my teammates and coaching staff."
Mason is the first All-American from Kansas since Thomas Robinson in 2012.
Hart, a senior who was key to Villanova's 2016 national championship, averaged 18.9 points and 6.5 rebounds for the Wildcats. He received 62 first-team votes.
"It was definitely a goal," Hart said of the All-America recognition. "Now that it happened, it's humbling. A great honor. I've got to thank everyone that voted for me."
Coach Jay Wright called Hart "the perfect combination of talent, hard work, intelligence and humility."
"He never let any single year's accomplishment deter him from getting better," Wright said. "I think he's one of the most complete basketball players in the country."
The sophomore Swanigan led the nation with 26 double-doubles and was the only player in Division I to average 18 points (18.5) and 12 rebounds (12.6). He shot 53.4 percent overall and 43.1 percent on 3s.
"He's a very knowledgeable guy, now he's been through it in terms of experience, understanding scouting reports and those types of things," Purdue coach Matt Painter said. "He really gets it. I think he really separated himself from a lot of people with the consistent play."
Ball, who has already declared for the NBA draft, took the country by storm as a freshman. He averaged 14.6 points, 7.9 assists and 6.1 rebounds while putting UCLA back on the national map in a hurry. He received 54 first-team votes.
Coach Steve Alford called Ball "very deserving of the recognition."
"He's been special for us all year," Alford said. "He's been an incredible teammate, and everything that he's done has been contagious throughout our team."
The last All-American from UCLA was freshman Kevin Love in 2008.
Jackson, who received 24 first-team votes, helped lead the Tar Heels to a second straight Final Four. The junior averaged 18.1 points and 4.6 rebounds this season.
"He's a better player overall," North Carolina coach Roy Williams said. "He's better defensively, better rebounder, he can score the basket and he's just had a year for us.
"He's been the leader of our team on the court, on the stat sheet. I couldn't be happier for him because he's really got it the old-fashioned way. He's worked, he's put in the sweat."
Nigel Williams-Goss of Gonzaga led the second team and was joined by fellow juniors Dillon Brooks of Oregon and Johnathan Motley of Baylor, sophomore Luke Kennard of Duke and freshman Malik Monk of Kentucky.
There has been at least one unanimous All-America pick the past four seasons.