The Frenchman has impressed in attack for the Gunners as of late, scoring five goals in his last six Premier League appearances, but has been linked with a move away from the Emirates Stadium at the end of the season.
Speaking ahead of Sunday's meeting with Premier League strugglers Fulham, Arteta said: "[Lacazette is] key, because in big moments and in key matches you need players and senior players who have this experience to make a difference for you.
"For me in his style and his development, even though he's 29, 30 years old, he's on the right path because he's ready to learn.
"He's doing things in a much better way than before and he really glues the team together. That's a quality that's not easy in a striker and he's got it.
"He's been really efficient and his momentum continues, the form that he's in continues and he's really important for the team."