Both fans and fellow co-stars took social media to express send their condolences after reports emerged the 26-year-old had passed away.
He had enjoyed a successful sporting career before appearing on the reality show in 2017 and also had spells at Ebbsfleet and Welling.
Mike did not enter the villa until partway into the series.
"His name was Mike Thalassitis, and every inch of my heart goes out to his family and friends".
"His name wasn't Muggy Mike".
"A good guy, taken far too soon".
Chris Hughes took to Twitter on Saturday night to lead the tributes to his former Love Island co-star.
Mike first rose to fame as a contestant on Love Island.
Mike was a semi-professional footballer and one of his old teams, Chelmsford City FC, has paid tribute to the sportsman. "You'll be missed so much you have no idea".
Mike, who was just 26, appeared on the 2017 version of the ITV2 dating show. Our thoughts and prayers go to his family and friends at this time.