The season ten contestant, who was eliminated from the singing competition two weeks ago, will appear on the ABC show on Tuesday night.
The performance was announced by co-host Tom Bergeron during this week's results show, with the presenter telling viewers that Toscano will be accompanied by her "close friend", professional dancer Mark Ballas.
The singer and Ballas sparked rumours that they were dating earlier this month when they were seen dining together in Los Angeles, although both have played coy on the speculation, insisting they are just friends.
Toscano previously revealed that she would "love" to appear on Dancing with the Stars, saying that she is a "huge fan" of the competition.
Other performers who have appeared on the current season of Dancing with the Stars in the past few weeks include Selena Gomez, Chris Brown and Toby Keith.