The 36-year-old is expected to depart Bayern Munich at the end of the season when his contract at the Allianz Arena is due to expire, which had resulted in speculation that Koln were keen on his services.
However, when asked about the rumour by Express, Koln's general manager Jorg Schmadtke said: "We are not used to discussing transfer rumours in public. Still, I am able to confirm there is no agreement between Cologne and Daniel van Buyten."
Meanwhile, Koln head coach Peter Stoger added: "I am very much surprised by this rumour."
As for Van Buyten's agent, Christophe Henrotay, he told Abendzeitung newspaper: "To me, this seems like a late April Fool's hoax. I don't know anything about this."
Van Buyten has made 13 appearances for Die Roten this season.