Cypripedium passerinum is a small multi-stemmed species with stems up to 18 inches in height. The mature stem has 3 to 5 leaves and up to 3 flowers. The petals and labellum are white with purple spots which are thought to resemble a sparrow's egg; the dorsal sepal is pale green.Cypripedium passerinum grows in spruce forests in thickets and openings, as well as bogs, tundra, and in coarse soils of terraces and stream banks.