Anthony's clutch shot was his team record-tying ninth trey of the game for New York, which won for the second time in three contests.
The Knicks drained 16-of-27 shots from long range overall.
J.R. Smith pumped in 18 points off the bench for New York, which held on for the win when Atlanta's Josh Smith misfired on a 3-point try at the buzzer.
Jeff Teague scored 27 points and Josh Smith scored 20 for the Hawks, who lost for the first time in four games.
Celebrity Families of 2014 [PHOTOS]