Bossiaea lenticularis is a slender spreading shrub that typically grows to a height of up to and is more or less glabrous. The leaves are mostly circular, long in diameter with stipules up to long at the base. The flowers are long, each flower on a pedicel up to about long with a few bracts up to long. The sepals are long joined at the base with bracteoles on the pedicel. The standardpetal is yellow with red markings, the wings yellow and the keel dark reddish with a paler base. Flowering occurs from August to September and the fruit is an oblong to egg-shaped pod long.