The Russian strongman's private life has been the subject of intense speculation since he and his wife Lyudmila announced in June they were divorcing after three decades of marriage.
In an interview with the Izvestia daily, Kremlin spokesman Dmitry Peskov said it was hard to say what Putin did in his private life as he works so much.
"What kind of a bloke he is, whether he has a wife or not, let us leave that to him and not interfere," Peskov said.
But in an unusual move, he directly responded to chatter on the Internet that Putin this weekend married gymnast Alina Kabayeva at a secret ceremony at the Iversky Monastery on Lake Valdai in northern Russia where the president had been attending a discussion forum.
"You understand that this is all from the realm of the imagination and it is useless to deny these (rumours) or call them rubbish. We have done this already a hundred times," Peskov said.
"The rumours stay alive, what can you do about them? But they have nothing in common with reality," he added.
The rumour had been started by a former government official in the Caucasus who wrote on his Twitter account that he had been told Putin had married Kabayeva at the monastery, which had been ringed off to the public.
It became widely spread after his tweet was retweeted by Russian protest leader Alexei Navalny, who has a substantial Internet following.
"Why the monastery was ringed off, I cannot tell you," added Peskov.
Rumours of an affair with Kabayeva have shadowed Putin for years, but the speculation has never been confirmed in any way.
The Moskovsky Korrespondent newspaper, owned by tycoon Alexander Lebedev, reported in 2008 that he was about to marry Kabayeva, 31 years his junior. The report was denied and the paper closed down shortly afterwards.
Putin then famously slammed people with "snotty noses and erotic fantasies" who interfered in other people's private lives.