The Dalai Lama "really is amazing," Tutu said after receiving the 2009 Spiritual Leadership Award at a Pretoria, South Africa, summit that also recognized the Tibetan Buddhist leader.
"He has an incredible serenity," Tutu said in a video posted on YouTube by the international Humanity's Team movement, which gave Tutu the award.
"Imagine, I mean, we praise (former South African President and earlier anti-apartheid activist) Nelson Mandela -- and we do, quite rightly -- for 27 years in jail and coming out with that magnanimity," Tutu said.
But "the Dalai Lama has been in exile 50 years," Tutu told an audience at a 2,000-seat outdoor amphitheater, "and you'd have expected that, by now, he would have been corroded by a bitterness. He hasn't."
"He's actually quite mischievous," Tutu said to audience laughter.
"I have to say to him: 'Look here -- the cameras are on us now. Try to behave like a holy man,'" Tutu said in mock seriousness, raising an index finger as if genuinely admonishing his fellow Nobel Peace laureate.
The retired Anglican archbishop made his remarks after receiving the award at the movement's 2009 Oneness Summit.
Humanity's Team of Boulder, Colo., has no religious or political affiliation, a movement spokesman told United Press International.