The France international says the "extraordinary" Argentine is peerless while revealing he is flattered by alleged interest from PSG.
The France international is regarded as one of the most exciting attacking players in the game today, but even he concedes when it comes to skill, one diminutive dribbler stands head and shoulders above everyone else.
"Messi is class," Ribery told Telefoot. "There is him, and then there is the rest. What he does is extraordinary. He demands admiration."
While Ribery has nothing but respect for Messi and the Argentine's accomplices at Camp Nou, he insists Bayern is not perturbed by the prospect of going head-to-head with the revered Catalan outfit.
"Everyone is waiting for this game," Ribery said. "And it is well known that Barca are a great team, but we are not afraid of them."
Ribery, meanwhile, has recently been linked with a return to France, with Paris Saint-Germain. The 30-year-old is intrigued by Les Parisiens' project but said he would like to finish his career in Bavaria.
"PSG's interest? It's flattering," Ribery said. "[Sporting director] Leonardo, who spoke to me, is a very important person in PSG. The club is transforming.
"But I am very happy at Bayern and my desire is to finish my career here. And [the feeling] is mutual."
Ribery, who has been capped 72 times by his country, joined Bayern in 2007 for a reported 25 million fee from Marseille.