James collected 11 rebounds, Wade dished off six assists and Chris Bosh added 18 first-half points for the Heat, who led the contest from start to finish.
Ray Allen came off the bench to supply 15 points, six assists and six rebounds for high-scoring Miami.
The Suns, meanwhile, dropped their second straight despite 15 points and eight rebounds from Luis Scola.
Shannon Brown chipped in 18 points, while Marcin Gortat provided 12 and 13 rebounds for the losers.
Swim Week Miami Beach 2014 [PHOTOS]