The invention discloses an antifungal medicament for treating skin tinea and a preparation method thereof. The medicament mainly comprises sweet wormwood volatile oil, divaricatus and rhubarb as raw materials to prepare effective components, and a pharmaceutically acceptable vector is added to prepare the medicament for external use. The medicament and the manufacturing method of the invention are unique, have a wide antifungal spectrum, obtain good curative effects for treating tinea capitis, tinea corporis, tinea cruris, tinea manuum, tinea pedis, tinea unguium and senile pruritus through clinical experiments, and have no toxic side effects on a human body and viscera.