Kemp was found floating at a beach in Montego Bay Thursday morning, Jamaica police said, reported New York Daily News.
No cause of death had been determined, police said.
Cops believe Kemp arrived in Jamaica on a cruise ship and was on vacation, but added that they did not have further details.
Kemp moved to New York from the Bahamas in 1979 with his band Kinky Fox. He released his self-titled debut album in 1986 and he scored a minor hit with "Just Another Lover."
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The song reached number 1 on the US Billboard R&B chart.
Kemp appeared on a 2007 Keith Sweat DVD called "Sweat Hotel Live" and had been performing at musical events across the US in recent years.
Fans flocked to social media to lament the pop singer's passing.
"RIP, Johnny Kemp. Thank you for the great music," NSYNC singer Chris Kirkpatrick tweeted.