The shutout was the 16th of DiPietro's career and the first for Coach Jack Capuano since he took over for the fired Scott Gordon five games ago. New York hadn't won since an Oct. 21 decision over Tampa Bay.
The Islanders' offense came from Jesse Joensuu, who got his first goal this season in the first period, and Rob Schremp, who got his second of the season in the second.
"It's a good feeling for the boys," Capuano said. "The key was to get through the neutral zone and get pucks to the net and we did a good of that for about two periods and then the tide turned. The penalty kill came up big for us in the third."
The loss busted the Devils' modest, two-game win streak. John Hedberg made 18 saves for New Jersey.