The 'Promiscuous Girl' hitmaker, who has previously appeared on the small screen in 'Roswell' and 'One Life to Live', will be performing in the episode, reported E! Online.
Carmen Electra is also in the next series on the show on its 100th episode, playing a character called Vesta, who is a cross between Dita Von Teese and a Pussycat Doll.
Furtado and the former 'Baywatch' actress are the latest in a number of high-profile stars to appear in past instalments of the series, including Billy Ray Cyrus and Kellie Pickler.
Other musicians to have appeared in the show include Snoop Dogg, DJ Samantha Ronson and Christina Aguilera.
Carly Rae Jepsen will be appearing in the first episode for the season five of '90210' - which also stars Jessica Lowndes, AnnaLynne McCord and Michael Steger - to be shown on October 8.