吉贝（学名：Ceiba pentandra），又名吉贝木棉、美洲木棉、爪哇木棉，为锦葵科木棉亚科吉贝属的植物。

落叶大乔木，高可达30公尺，径25~50公分；树干通直，初为绿色，具有多数的瘤刺，老则为灰褐色，且无针刺；树枝水平伸展，轮生，绿色；掌状复叶有长柄，小叶5～8枚；春季开白色或淡红色花；长圆状椭圆形木质的蒴果五裂，果瓣内密生丝状绵毛。

Ceiba pentandra is a tropical tree of the order Malvales and the family Malvaceae (previously separated in the family Bombacaceae), native to Mexico, Central America and the Caribbean, northern South America, and (as the variety C. pentandra var. guineensis) to tropical west Africa. Kapok is the most used common name for the tree and may also refer to the cotton-like fluff obtained from its seed pods. The tree is cultivated for the seed fibre, particularly in south-east Asia, and is also known as the Java cotton, Java kapok, silk-cotton, Samauma, or ceiba.