Messi's current deal runs until 2021, the same year he turns 34, but the Argentinian has been in brilliant form again this season.
He has 42 goals for club and country while his 32 scored in La Liga have propelled Barca to within touching distance of their fourth league title in five years.
"We would like to renew his contract, that's the idea," Bartomeu told ESPN in an interview published on Friday.
"I believe he still has many years in front of him and in the coming months we will sit down with him so that he has many more years at Barcelona."
Messi joined Barcelona's academy aged 13 and is one of the few players left from Pep Guardiola's iconic team that won the treble in 2009.
In total, he has won nine La Liga titles with the club, as well as four in the Champions League and six in the Copa del Rey.
"Messi is a one-club man," Bartomeu added. "It's more than what he does on the pitch, his relationship with Barca will last forever.
"I use the example of Pele, who was always at Santos. We want Messi to always be at Barca, whether that's playing on the pitch or being linked to the club (after he retires)."