Messi won the Fifa Ballon d'Or for the third time in succession earlier this year, and is considered by many to be one of the best ever.
However, 65-year-old Tostao feels that the Barca striker still has some way to go before he can be considered Pele's equal.
"Even if you do not take the cold numbers of how many trophies he has won and how many goals he has score into account, I have no doubt about it that he [Messi] is already better than Maradona," Tostao said to Globoesporte.
"Many will disagree because he has not won a World Cup or scored a wondergoal in a big game at the World Cup, but at his current level he is only behind Pele in my opinion.
"Pele was more complete and had qualities that Messi lacks. He scored many headers for example, and make excellent use of his body."
Messi has already netted 35 goals in 28 La Liga appearances in the 2011-12 season.