The man was walking on the sidewalk in the 200-block of West Illinois Street about 8:50 a.m. when a shattered window hit him, CPD said.
He suffered minor cuts to his forehead and ear, but was treated and released on the scene, police said.
RELATED: Chicago weather forecast: Snowfall begins ahead of 1st measurable accumulation of season
A rain/snow mix fell across the Chicago area Tuesday morning.
It was not immediately clear what caused the window to fall.
This is a developing story; check back with ABC7 Chicago for updates.