Mbappe, 22, has been widely tipped to follow in Ronaldo and Messi's footsteps as one of the next dominant football superstars.
The Paris Saint-Germain forward, who has been heavily linked with Real Madrid, was in excellent goalscoring form for his club last season.
Mbappe scored an impressive 42 times in 47 appearances across all competitions, despite PSG conceding the Ligue 1 title to Lille.
Eto'o has insisted that Barcelona captain Messi and Juventus superstar Ronaldo are the world-class players who "mark current football with the highest grades."
The 40-year-old Cameroon legend, who played alongside Messi at Barcelona, has now suggested that Mbappe will become a "God."
Speaking to Argentine newspaper La Nacion, Eto'o said: "Cristiano is another God. Together with Messi, they are the players who mark current football with the highest grades.
"But another God is coming for when Messi and Cristiano get tired of giving us these joys. That new God will be Kylian Mbappe."
Messi's current deal with Barcelona will expire at the end of this month as the Spanish club are locked in negotiations over a new contract.
The 34-year-old Argentine superstar has been linked with both PSG and Manchester City amid uncertainty surrounding his future at the Camp Nou.
However, Eto'o has teased that Barcelona president Joan Laporta is preparing a "reliable, interesting project" for his former teammate.
"I can't imagine Leo with another shirt. It is his club, his home, his love," he added.
"I do not think that his continuity is due to a question of money. Leo is Barcelona and Barcelona is Messi.
"I know Laporta is preparing a reliable, interesting project for him."
Featured Image Credit: PA
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