The special will air on Oxygen.com directly after the Season 2 winner is crowned Tuesday.
Leakes is best known for her appearances on "The Real Housewives of Atlanta" and "Glee."
Ulrich is an on-air mentor and casting director for "The Glee Project."
Also making a special appearance during the live reunion will be the cast from Oxygen's new dance series "All the Right Moves."
The winner of "The Glee Project" will be featured in a seven-episode arc on the musical dramedy series "Glee."