Jordan Eberle had a goal and an assist, Michael Dal Colle scored his first NHL goal, and Nick Leddy had two assists for New York (27-15-4), which has won 13 of its past 16 games. Robin Lehner made 16 saves for his 10th win in his past 11 games.
"We take it day by day," Lee said. "You don't look ahead at anything and you continue to just get back to work. As awesome as it's been and as great as it's been, nothing's happened. We still have a lot of hockey left. We're just trying to continue to get better every day."
WATCH: [All Devils vs. Islanders highlights]
Andy Greene scored, and Mackenzie Blackwood made 22 saves for New Jersey (18-22-7), which has lost five of its past seven games and has allowed at least four goals in five of its past six.
"We have to continue to work on being stronger in front of our net. That's something we've talked about," Devils coach John Hynes said. "We've got to do a better job coaching the guys, we've got to have guys that are willing to play in that area of the ice and take pride in that area of the ice."
The Islanders scored three goals on five shots in the first period.
Lee gave them a 1-0 lead at 5:48 when he redirected Leddy's shot from the left point.
Dal Colle made it 2-0 at 9:19 when he parked in front of the net and got his stick on Scott Mayfield's low slap shot from the right point.
"I can't really describe it," said Dal Colle, the No. 5 pick in the 2014 NHL Draft. "I've envisioned it for so long, ever since I started playing when I was like 4. All the work I've put in and all the sacrifices my family's made for me to be able to play this game, I think it's just a special moment for my family."
Eberle scored a power-play goal at 15:12 when he took a pass from Leddy and roofed a wrist shot from the left face-off circle to make it 3-0.
