Griezmann said Ronaldo is a “source of inspiration for everyone”, adding that the Juventus forward is a complete player.
Both France and Portugal played on Saturday but fell short of the results they wanted.
France drew 1-1 with Hungary in Budapest, while Portugal lost 4-2 against Germany.
“He [Ronaldo] is a source of inspiration for everyone,” Griezmann told a pre-match press news conference.
“It is extraordinary what he is doing at 36 years old. He and Messi, there will be no one like them, we are lucky to meet them on the field.
“He is a complete player, an example for all young and old, he can show the way for many young people.”