The Spain international says the Catalans are "a very balanced outfit and have the best player in the world" in Argentine attacker Lionel Messi
The Bavarians are widely regarded as the form side in world football, having wrapped up the Bundesliga title with a record six rounds to spare and stormed into the last four of the game's premier club tournament with a resounding 4-0 aggregate win over Italian champions Juventus.
However, Martinez, speaking ahead of Tuesday's first-leg clash with Barca at the Allianz Arena, is extremely wary of the threat posed by the Blaugrana to Bayern's hopes of atoning for defeat by Chelsea in last year's Champions League final.
"Unfortunately, everything about them worries me," the Spain international is quoted as saying by AS. "They're a very balanced outfit and they have the best player in the world.
"And even if [Lionel] Messi has a bad day, he has plenty of team-mates who can do a very good job, such as Pedro, Alexis [Sanchez], [David] Villa, Xavi, [Andres] Iniesta, etc."
Indeed, Martinez believes there is virtually nothing to choose between these two genuine European superpowers.
"I think it's the perfect moment for us to take on Barca," the former Athletic Bilbao man claimed. "The problem is that they're also in good form!"
Still, Martinez is looking forward to the challenge, particularly from a personal perspective, as he is keen to pit his wits against the player he believes to be the best in his position.
"Sergio Busquets is the key cog in the Barca machine," he stated. "There are other players who grab the headlines, but if this Barca side has won so many titles it's thanks to him.
"He always holds his position. He brings other players to life, such as Xavi or Iniesta. They can join in the attack knowing that he's got them covered."
Martinez, who can also play in defence, joined Bayern from Bilbao last summer for a reported €40 million.