Joanna Page has taken on a new role as ambassador for the PDSA and will help the charity raise £6 million in funds for three new pet hospitals.
The Gavin and Stacey actress, who has a dog called Daisy, said pets are an extremely important part of people's lives and she could not bear to be without her own pet.
She said: "PDSA helps hundreds of thousands of sick and injured pets, saving lives every day of the week and this service is funded entirely by public support.
"Giving the gift of life to pets in need is no mean feat, so supporting them was a very easy decision for me."
Ms Page added that she will be a hands-on ambassador and has always wanted to work with animals.
She said she looks forward to sitting in on consultations, observing operations and meeting the pets treated by the charity.
The three new hospitals will replace out-dated buildings in Cardiff, Plymouth and Birmingham.
The PDSA has 50 pet hospitals across the UK and the cost of its services over 2012 will amount to £60 million.