It is endemic to northern California,[1] where it is known from only four occurrences in the North Coast Ranges, including near Anthony Peak.

[2] Lupinus antoninus grows in mountain forests often amongst firs.

This is a hairy, erect perennial herb growing 20–50 centimetres (7.9–19.7 in) tall.

The flower is whitish with a light brownish wash on its banner.

The fruit is a silky-haired legume pod up to 3.5 centimetres (1.4 in) long containing a few mottled brown seeds.