The show, which focuses on a group of people living on a game park in South Africa, was confirmed for a seventh series earlier this year.
Bathurst is to play Ed Lynch, a talented veterinary surgeon who also excels in business. When Ed is first introduced, he is running the animal park which he has transformed from a run-down zoo to a successful establishment.
Bathurst revealed that he is "looking forward" to acting in the programme.
"I'm very excited Ed is going to be shaking things up in Leopard's Den," he commented. "Wild at Heart is one of the most successful dramas of the last decade and I'm thoroughly looking forward to filming the new series and working with the rest of the cast."
Bathurst will join series regulars Stephen Tompkinson, Dawn Steele, Hayley Mills and Deon Stewardson.
Earlier this year, Tompkinson revealed that he still enjoys working on Wild at Heart but admitted that filming with the animals can be difficult.