The Blades have had a close partnership with the Australian A-League side for a while and have held reciprocal fact-finding missions amongst other initiatives.
"It is exciting to have a businessman of Kevin's calibre, with a proven dedication and commitment to football to come on board," said Mariners deputy chairman Peter Turnbull.
"We look forward to utilising his immense knowledge on the business of football and his experience in property development. We also look forward keenly to his input with the new centre of excellence development at Tuggerah as Kevin has already been heavily involved in building world class centres in several cities around the world."
McCabe added: "In the UK we are known as the "family club" and as such we were immediately drawn to the club that has those same views and ideals in Australia - the Mariners.
"Their commitment to family and community programs are second to none. I am proud to join the board and look forward to being able to assist the club in realising its long-held dreams."