Two men have been jailed for life over a double murder on Queensland's Gold Coast.

A Supreme Court jury in Brisbane found Vladimir Garcia and Cameron Stewart guilty of killing Sandie Davie and his wife Suzanne Davie in May 2009.

The accused men had previously worked for the Davie's security firm.

Mr Davie was found dead bound and stabbed in a toilet block, while he was on patrol at West Burleigh.

The word 'dog' was written in his blood on the toilet door.

Later that day, Mrs Davie was discovered dead at the couple's Robina home.

Garcia and Stewart will serve a minimum of 25 years in jail.