Adam Larsson and David Clarkson each scored their first goals of the play-offs to spark the third period rally, with Clarkson barging in to poke home a rebound that left him leaning over the cross-bar.
Travis Zajac and Bryce Salvador added the final two goals for the Devils, who played without regular season leading scorer Ilya Kovalchuk due to the injury he sustained in Game One, to send the series back to New Jersey for Thursday's Game Three.
Dainius Zubrus added two assists for the Devils.
Matt Read had put the home team ahead 1-0 in the first period before New Jersey broke through in the third against Philadelphia goaltender Ilya Bryzgalov, who had been flawless in the first two periods and finished with 31 saves.
The Flyers had grabbed the series lead in overtime in Game One, but on Tuesday New Jersey controlled the tempo throughout until finally letting loose in the final period.
"I think having a one-goal lead we just kind of came out on our heels and we didn't give them the respect they needed," Read said.
"They are a great hockey team. We came out flat and they took advantage of that and outplayed us in the second and the third."