Welsh international Ramsey, who has entered the final year of his current deal, has previously admitted that he is unsure about his future and confirmed that his agent is in contact with Arsenal chiefs over a potential exit.
Speaking to reporters, French forward Lacazette labelled Ramsey an Arsenal "legend" and added that the midfielder can have an important influence in the Gunners' team this season.
"Ramsey is really important," the striker said. "Aaron is there for maybe 10 years, he's a legend in the club so we have to be respectful for everything he has done.
"Of course with his quality he can help the team to be better. He's an example for all the young players. Of course we need Aaron in the team."
Ramsey has scored 36 goals in 234 Premier League appearances since joining Arsenal in 2008.