Hibiscus or Rosemallow is a large genus of about 200-220 species of flowering plants in the family Malvaceae, native to warm temperate, subtropical and tropical regions throughout the world. The genus includes both annual and perennial herbaceous plants, and woody shrubs and small trees. The leaves are alternate, simple, ovate to lanceolate, often with a toothed or lobed margin. The flowers are large, conspicuous, trumpet-shaped, with five or more petals, ranging from white to pink, red, purple or yellow, and from 4-15 cm broad. The fruit is a dry five-lobed capsule, containing several seeds in each lobe, which are released when the capsule splits open at maturity.

Many of these species are grown for their showy flowers and many are used as landscape shrubs. Hibiscus syriacus (Mugunghwa or "Rose of Sharon") is the national flower of South Korea, while Hibiscus rosa-sinensis (Bunga Raya or "Chinese hibiscus") is the national flower of Malaysia. The ma‘o hau hele (Hibiscus brackenridgei) is the state flower of Hawai‘i.

In temperate zones, probably the most commonly grown ornamental species is Hibiscus syriacus, the common garden Hibiscus, also known in some areas as the "Rose of Althea" or "Rose of Sharon" (but not to be confused with the unrelated Hypericum calycinum, also called "Rose of Sharon"). In tropical and subtropical areas, the Chinese hibiscus (H. rosa-sinensis), with its many showy hybrids, is the most popular hibiscus.

Hibiscus species are used as food plants by the larvae of some Lepidoptera species including Chionodes hibiscella, Hypercompe hambletoni, The Nutmeg and Turnip Moth