The body was found by a dog walker on the beach between the Little Groves caravan site and the Isle of Sheppey Holiday Village just before 6am on Wednesday morning.
Kent Online reports that the man, thought to be in his 30s or 40s, died of serious head injuries. He had been "savagely beaten" and was left naked from the waist down, although officers said there was no evidence of sexual assault.
According to the Mirror, the Kent and Essex Serious Crime Directorate has launched a murder inquiry.
Detective Chief Inspector Jon Clayden told the BBC: "The injuries that had been sustained were clearly caused by other parties.
"It was a vicious attack that had been subjected to the gentleman, clearly with the intent to kill him."
Clayden told Kent News: "We would like to speak to anyone who may have seen or heard anything on or near this stretch of beach between 8pm on Tuesday and 6am on Wednesday morning."
But, according to Kent Online, he added: "We want to keep an open mind [to when he was attacked] - we have not limited it to last night. We are making enquiries with holidaymakers at the caravan site.
At the end of July, a woman's body washed up on a beach in Suffolk.
The body of the woman, described as "elderly", was spotted by two members of the public on the beach at Shingle Street, near Hollesley.
Just days before, the body of a woman in her 30s was discovered by a walker on a beach in East Lothian, Scotland.
And, back in June, the body of a woman was found on Winterton Beach, near Great Yarmouth in Norfolk.
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