The 24-year-old joined the Bavarian giants from Athletic Bilbao in the summer for €40m (£32m).
"He has to adapt to his new surroundings a bit," Neuer is quoted as saying by Spox.
"The Spanish league is different to the Bundesliga. That's why people cannot expect too much from him right away. He will do a good job eventually, though.
"He's a very open guy and the good thing is that he speaks English pretty well for a Spaniard."
Bayern have won both games in the Bundesliga so far this season.