The Australian television and radio personality, who was recently romantically linked to aspiring model Rochelle Fox, posted a picture and a message on the geosocial network on Saturday night (March 3).
Sandilands - who named himself "Big gold mic" - posted a shirtless photo and added the message: "Happy Mardi Gras darls x."
Grindr is a smartphone app which uses geolocation to allow members to see profiles of other members who are nearby.
His manager later told The Daily Telegraph: "He did it as a joke. He was filming for Australia's Got Talent and someone had Grindr on their phone, so he thought it would be funny to create a profile."
Sandilands hit the headlines late last year when he launched an on-air tirade against a female journalist who criticised his TV show, labelling her a "fat slag" and a "little troll", causing various sponsors to withdraw their support from his breakfast slot.
He has also reportedly angered his radio bosses and sponsors for taking sick days recently, but friend Brian McFadden revealed that he is concerned for Sandilands, saying: "[He's] been really down. I think everything's getting on top of him."
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