Phoenix sylvestris ranges from 4 to 15 m in height and 40 cm in diameter; not as large as the Canary Island Date Palm, but nearly so, and resembling it. The leaves are 3 m long, gently recurved, on 1 m petioles with acanthophylls near the base.
The leaf crown grows to 10 m wide and 7.5 to 10 m tall containing up to 100 leaves. The inflorescence grows to 1 metre with white, unisexual flowers forming to a large, pendent infructescence.
The single-seeded fruit ripens to a purple-red colour.