The former Blue Peter presenter is the final contestant to be confirmed for the new series of the BBC ballroom show, which returns next month.
The news was announced on Claudia Winkleman’s Radio 2 show on Saturday morning.
Helen said in a statement: “I’m really excited to get stuck into a fun adventure. My family and friends have always loved the show and can’t wait for me to get started.”
Helen began her broadcasting career hosting Blue Peter between 2008 and 2013, and is a regular face on Countryfile and BBC Sports coverage.
She was also recently confirmed as the new host of Radio 5 Live’s Sunday morning slot, after Laura Whitmore announced her departure.
Strictly Come Dancing returns to BBC One next month.