- As a writer and animator for Sesame Street, Willems won six Emmy Awards between the years of 1995-2001.
- Willems won several ASIFA-East Awards for his "Suzie Kabloozie" segments on Sesame Street.
- Willems won the Caldecott Honor Award for his books:
- Don't Let the Pigeon Drive the Bus! (2004)
- Knuffle Bunny: A Cautionary Tale (2005)
- Knuffle Bunny Too: A Case of Mistaken Identity (2008)
- Willems's book, Leonardo, the Terrible Monster, was named one of Time Magazine's 10 Best Children's Books for 2005 and a Book Sense Book of the Year Honor Book in 2006.
- Willems was awarded the Carnegie Medal for animated versions of his books:
- Knuffle Bunny (2007)
- Don't Let the Pigeon Drive the Bus! (2010)
- Willems won the Theodor Seuss Geisel Award for his books:
- There Is a Bird on Your Head (2008 Medal Winner)
- Are You Ready to Play Outside? (2009 Medal Winner)
- We Are in a Book! (2011 Honor Book)
- Willems was a NAPPA Award Winner for the animated version of his book:
- Don't Let the Pigeon Drive the Bus! (2010 Gold Winner)
- The New York Times Book Review called Willems, "the biggest new talent to emerge thus far in the 00's" and Pigeon, "one of this decade's contributions to the pantheon of great picture book characters."
