Eriosema dregei is a small, low-growing evergreen shrub that grows up to 400 mm tall. It has a woody underground rootstock producing 4-10 stems that grow upright, branching out from the base, giving the plant a bushy shape. They are covered with fine silver hairs, giving the stem a slightly rough texture. The leaves are trifoliolate, which means they have three leaflets. The leaflets are oval with a pointed tip and have a smooth texture. The upper surface of the leaf is covered with white hairs while the underside is densely covered with white to silver woolly hairs. The veins of the plant are a noticeable yellowish colour. The leaflets are vibrant green, and they grow 30-70 mm in length.

The plant produces yellow to orange flowers from late winter to spring. The flowers are formed in clusters; they grow where the leaves meet the stem and rise well above the foliage. Each cluster may contain up to 67 flowers. Each flower has 5 petals and a calyx densely covered with silver hairs. After flowering Eriosema dregei produces small, rounded pods covered with a mix of long reddish-brown hairs and short white hairs. When the fruit is ripe, it turns brown and often remains on the plant even after releasing the seeds. The seeds are oval, hard, pale chestnut brown and about 6 mm long.  

Eriosema dregei has consistently been confused with E. umtamvunense and E. luteopetalum. It differs from E. umtamvunense with its yellow to orange flowers (not red and yellow as in E. umtamvunense) and from E. luteopetalum it differs with its stem covered with fine silver hairs (not a golden-brown stem with short yellowish hairs as in E. luteopetalum).