Cowdrey will begin his new role on 17 December. He has previously worked at World Wildlife Fund as the head of press and media relations and as a campaign director.
He has also worked in media, marketing and publications roles for the Environment Agency and National Rivers Authority.
Cowdrey said: ‘I’m very excited to be joining the RSPCA at such an important time in its history and look forward to developing a strong communications framework in driving the organisation's brand and profile forward.
‘This role will combine both my passion for communications and animal welfare and will help to inform and change public opinion on key campaigns like live animal exports, badger culling and responsible dog ownership.’
The appointment follows the news that the RSPCA has appointed former NSPCC director of child protection consultancy John Grounds as director of marketing and campaigns.
Cowdrey joins the RSPCA after a year in which Guide Dogs achieved national media coverage on campaigns including responsible dog ownership, while lobbying for compulsory microchipping.