The Ottawa native could bring some good luck to the Senators, who are down 2-0 in the best-of-seven series after a pair of losses to the Ducks in Anaheim. When she sang the national anthem at the their first game on Oct. 8, 1992, the Sens beat the Montreal Canadiens 5-3.
Other anthem singers so far at the final include Stephen Stills and Toronto's Holly Cole.
Lyndon Slewidge, Ottawa's official anthem singer, will perform at Game 3 on Saturday at Scotiabank Place.
Morissette, 33, has sold more than 40 million albums and won seven Grammy Awards.
She also sang her song "Too Hot" at the 1992 NHL Awards.