Citharexylem spinosum is a tree that reaches a height of up to 15 m (49 ft). The ovate to elliptic leaves are 4–20 cm (1.6–7.9 in) long and have orange petioles. Small white flowers are produced throughout the year on hanging axillary and terminal racemes and panicles 20–40 cm (7.9–15.7 in) in length. The fruit are red to black subglobose drupes 7–10 mm (0.28–0.39 in) in diameter.