Bupleurum lancifolium is a species of flowering plant in the family Apiaceae known by the common name lanceleaf thorow-wax. It is native to the Mediterranean Basin and it is known elsewhere, including parts of North America, as an introduced species. It grows up to tall with a hairless, waxy stem around which leaves are fused at their bases. The dull, waxy, deep-green leaves are narrowly lance-shaped to nearly oval and 3to long. The inflorescence is a compound umbel borne on a peduncle which may be several centimeters tall. The umbel is surrounded by five wide, round to oval, and sometimes pointed bractlets at the base. The flowers are yellow to yellow-green.