Saku Koivu scored the lone goal on assists from Cam Fowler and Teemu Selanne for the Ducks, who have won their past five games.
Dwayne Roloson was tagged with the loss as he gave up the goal on 14 shots for the Islanders, who are struggling through an eight-game losing streak.
It’s the first eight-game slide for New York since Jan. 2-19, 2009.
The first two periods passed scoreless as Roloson needed to stop just seven shots while McElhinney turned aside 18.
At the 3:40 mark of the third period, the Ducks took the lead.
After McElhinney made a couple of big stops at the Anaheim end, the puck went down the other end. Selanne took the disc into the New York zone down the left wing and left a drop pass for Fowler at the left circle. From there Fowler fired a pass over to the slot where Koivu blew a one-timer past Roloson.
McElhinney stopped all nine shots he faced in the third period and helped to kill off two New York power plays to help Anaheim hold on for the win.
Anaheim hosts Dallas on Friday…The Isles continue their west coast swing in San Jose on Thursday…The Ducks have taken three of the last four against the Islanders…The Islanders have been held to two goals or less in each of their last six games and have been outscored 32-12 on their eight-game slide…Anaheim has won five straight for the first time since Jan. 5-13 last season.