Sudeikis will portray lead George Bailey who gets to see what life would have been like if he never existed. Wendt will take on the role of Uncle Billy.
Tom Bergeron is serving as the host. The table read will also pay tribute to Asner and feature surprise musical performances, an interactive live Q&A session with the cast and pay tribute to Mark Darnell, president of Warner Bros. unscripted and alternative television.
The Ed Asner Family Center promotes mental health and enrichment programs to children with special needs.
The live table read will stream online on Dec. 5 starting at 8 p.m. EST through Teafc.org. Tickets are on sale now.
Asner, a seven-time Emmy Award-winning actor known for The Mary Tyler Moore Show, Up and more, died at the age of 91 in August.