Oklahoma City snapped a two-game skid, taking a four-point lead into the final period and then slowly pulling away after Orlando had tied it with 3:55 to play.
Durant had 25 points and seized eight rebounds. Russell Westbrook pitched in 19 points and Serge Ibaka had 14 points to go with 13 boards.
Orlando lost its sixth straight game despite a 25-point performance from Maurice Harkless.
The Thunder, one of four NBA teams with at least 20 road victories this year, won their 21st away from home.