Anthony made 16 of 18 free throws and also was called for a flagrant foul for the fired-up Knicks, who have fallen behind Indiana into third place in the Eastern Conference and whose Atlantic Division lead over the Brooklyn Nets is down to two games.
They were sharp enough to build a couple of big leads and turn away the runs Philadelphia made, handing the 76ers their eighth straight road loss.
All-Star Jrue Holiday had 30 points, five rebounds and five assists for the 76ers, who have lost five straight overall. Evan Turner had 21 points and Thaddeus Young added 11 points and 10 rebounds after missing six games with a strained left hamstring.
Knicks coach Mike Woodson declined to make a lineup change, and it was Stoudemire and the reserves who helped New York take control early in the second quarter, and the starters who reopened a big lead to begin the third.
Raymond Felton finished with 14 points despite bruising his right heel and J.R. Smith also had 14 for the Knicks.
76ers coach Doug Collins said he expected the Knicks to be "testy" and "edgy" and that was the case with about 7 1/2 minutes left in the third quarter and the Knicks leading by 14. Anthony appeared to hit Hawes behind the head, and when they began to exchange words, Chandler rushed in and shoved Hawes back. Anthony ended up called for a flagrant foul, and Chandler and Hawes were whistled for technical.
The 76ers rallied a bit afterward, getting within 76-67 at the end of three, but then Stoudemire scored the first four of the final quarter and Philadelphia didn't really get close again until the final minutes.