The directors of Unidos de Vila Isabel samba group told G1, Globo TV's Web site, that Bundchen has just accepted their invitation to appear in their parade. Her costume and float have not been decided yet.
Brazil's 2011 Carnival will fall in the second week of March. Samba groups spend up to $5 million each on their parades, competing fiercely for first place and the attention of millions.
Unidos de Vila Isabel came in fourth in this year's competition.
The Brazilian model is married to U.S. football player Tom Brady.