This tree is one of two species which yield the valuable Lignum vitae wood, the other being Guaiacum officinale. This small tree is slow growing, reaching about 7m (23ft) in height with a trunk diameter of 50cm (20in). The tree is essentially evergreen throughout most of its native range. The leaves are compound, 2.5–3cm (0.98–1.18in) in length, and 2cm (0.79in) wide. The purplish blue flowers have five petals each, and yield yellow pods containing black seeds encapsulated separately in a red skin.
Guaiacum sanctum is the national tree of the Bahamas.