Mustafi headed the crucial opener in Arsenal's 2-0 win over Tottenham on Saturday and produced an excellent defensive display to prevent Harry Kane adding to his north London derby tally.
A thigh injury in October kept Mustafi out for six weeks but Arsenal are yet to concede in the Premier League this season when he has partnered Laurent Koscielny in defence.
Wenger believes Mustafi brings greater organisation to his back line and compared the German to compatriot, and now 33-year-old Arsenal club-mate, Mertesacker.
"First of all, he's similar to Per on a mental front, but of course he's 10 years younger, and he's a leader, he's a motivator," Wenger said.
"He has a strong focus, and he's strong in the challenge. He had an outstanding performance against Tottenham. In the air he was good. He started a bit nervy and slowly became stronger and stronger."