Goran Dragic scored 17 points and handed out five assists for Miami, which got 16 points and 11 rebounds from Willie Reed.
Dion Waiters and Tyler Johnson each scored 15 for Miami. Waiters made a 40-footer to end the first half while Wayne Ellington added 12 for the Heat. Miami was 11 for 11 from the foul line.
Serge Ibaka scored 15 points and grabbed nine rebounds for Orlando. Elfrid Payton shot 1 for 8, missing his final six shots, while Evan Fournier scored 10 for the Magic, who missed 16 of their first 17 tries from 3-point range. Orlando was held to 19 points or less in three of the four quarters.
Next up for the Magic is New Orleans on Thursday at the Amway Center. Orlando (1-5) will host the Heat on Oct. 26 for the start of the regular season.