Route 187 is a short segment of highway running less than five miles (8 km) in Howard County, Missouri.

Its eastern terminus is at Route 87 south of Glasgow; its western terminus is at Boone's Lick State Historic Site.

Route 187 begins at Boone's Lick State Historic Site in Howard County, where the road continues west as CR-328.

The route heads northeast on a two-lane undivided road, passing through areas of fields and woods.

[1] The entire route is in Howard County.