Tobey Maguire could use a shave, because he looks like he has more important things on his mind.

The actor ventured out in L.A. Monday ... the first time he's been seen since announcing he and his wife were splitting up after 9 years of marriage. Spidey's still wearing red these days -- but gym shorts aren't quite as cool.

Maguire's ex, Jennifer Meyer, was seen out in public last week ... and she seemed pretty chill.