The Belgian shined while enjoying a similar spell with West Brom last season - netting 17 goals in 35 Premier League appearances - and Martinez has backed him to continue developing at Goodison Park.
"He's still a young man but he's got everything," Martinez told the club's official website.
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|8/1||Romelu Lukaku is 8/1 with Coral to score two or more v Scotland on September 6
Lukaku moved to Chelsea for a reported fee of £17 million two years ago, but struggled for first-team appearances during his debut season.
And Martinez has praised Lukaku's professionalism and feels his arrival will give the Everton squad a "real boost".
Martinez continued: "What he's achieved already is impressive. Probably the biggest point is that we all feel it is time to kick on and carry on achieving.
"He had a massive move at a very young age and we all know what he's capable of doing in the Premier League.
"He's not someone that hasn't had an impact in the league; he's someone that, at just 20 years old, has huge potential. He's part of a very talented generation in Belgian football.
"As a human being, he is an incredible character and a very intelligent man. I can't wait for him to join us and he's going to give us a real boost into the squad."