Lamar Odom added 15 points and 11 rebounds for the Americans, who won gold in the worlds for the first time since 1994 and a fourth time overall. They did it with a team without the big name NBA superstars from the 2008 Olympic gold medal team.
Hedo Turkoglu of the Phoenix Suns scored 16 points for the Turks, who were bidding for their first title and were boosted by huge crowd support, with fans in red filling most of the 15,000-seat Sinan Erdem Dome.
Lithuania beat Serbia for the bronze earlier in the day.
Durant, who scored 33 and 38 points in the previous two games, again led the offense as the US qualified for the 2012 London Olympics. He made seven three-pointers.
Durant, the NBA scoring champion at Oklahoma City, was voted the most valuable player of the championship. He left the court with 42 seconds left and shared a long hug with coach Mike Krzyzewski, who finally won the world title after his previous two attempts ended with bronze medals.
The US victory put a disappointing end on an important day for Turkey, which approved sweeping changes to its constitution in a referendum vote, which the government hailed as a leap toward full democracy.
President Barack Obama called Prime Minister Recep Tayyip Erdogan before the game, congratulating him on the success of the tournament and Turkey's team while acknowledging "the vibrancy of Turkey's democracy as reflected in the turnout for the referendum." But the Turkish team, serenaded throughout by fans singing "12 Giant Men," its theme song since its runner-up finish while hosting the 2001 European championship, fell short of becoming the fourth host to win the world championship and first since Yugoslavia in 1970.
The Turkish players were a step slow and consistently beaten on the boards, perhaps drained from their thrilling 83-82 victory over Serbia in Saturday's late game.
With Kobe Bryant, LeBron James, Dwyane Wade and other US
stars sitting home, this American group was called a "B-Team," which the players used as motivation to prove they were capable of winning the title.
The Americans already knew they'd be bringing a different team to Turkey after all the gold medalists from the 2008 Olympics opted to take this summer off. Then All-Star forward Amare Stoudemire and David Lee were forced to withdraw on the opening day of training camp.
The US was left with a young, undersized team, featuring six players 22 or younger and only one true center in Tyson Chandler, who quickly became a backup when forward Odom was installed as the starter.
These Americans produced where many of their bigger-name predecessors couldn't four years ago at the worlds in Japan. They began to silence the raucous Turkish home crowd midway through the second quarter with a superb defensive effort.
Durant scored 20 points in the first half, then hit consecutive 3-pointers early in the third quarter, yelling at Turkish fans sitting courtside and pounding his chest after the second, as the US quickly extended a 10-point halftime lead.
The whistling was so loud when US players were introduced that it was hard to make out the names. There were more whistles and boos every time the Americans had the ball in the early going, and the building was at its loudest when Turkoglu made consecutive 3-pointers to give Turkey its first lead at 15-14 with 4:07 remaining in the first quarter.
The US held Turkey to one field goal over the first 6 minutes of the second quarter, extending the lead to 10 on a 3-pointer by Durant. The Americans were ahead 42-32 at halftime.
FIBA inducted its Hall of Fame class at halftime, a group that included women's star Cheryl Miller, former NBA centers Vlade Divac and Arvydas Sabonis, and Brazilian star Oscar Schmidt.
