Edmonton won for the fourth time in five games, getting 28 saves from Mathieu Garon.
The Oilers managed only 18 shots against Evgeni Nabokov, but three of them got past the San Jose goaltender in the Sharks' second straight loss.
Joe Pavelski produced a goal on a slapshot with 3:17 remaining in the second to get the Sharks within one, but Pisani's goal 3:33 into the third restored the two-goal cushion.
Mike Grier brought San Jose back within a goal at the 8:34 mark, but Edmonton could not solve Garon again. Garon was coming off a 38-save effort in a win over Minnesota Tuesday.