Icaricia lupini, the lupine blue, is a butterfly of the family Lycaenidae.

It is found from south-western Canada, south through much of mountainous and intermountain western United States and high plains to northern Mexico.

Adults are on wing from June to August in one generation in the Sierra Nevada of eastern California.

The hairs of the caterpillars can cause skin irritation (urticaria).

Media related to Icaricia lupini at Wikimedia Commons