The invention discloses a body odor removing active agent and a preparation method thereof. The active agent comprises the following required raw materials: a solvent, a deodorant, an emollient, a moisturizer, an emulsifier, a skin conditioning agent, an emulsion stabilizer, a preservative, a thickener, an antioxidant, a pH regulator and an aromatic, and the raw materials are divided into a phase A, a phase B, a phase C and a phase D. According to different mechanism of body odor formation, and by combining the scientific ratio of Chinese and Western medical theories, the plant active ingredients capable of removing body waste by aromatic properties, dispelling wind, dehumidifying, resisting perspiration and deodorizing, as well as a secret recipe for treating the body odor, are selected to improve the human skin protection ability; the recipe can improve the transdermal absorption ability of the active ingredients, and the active ingredients are firmly adhered to the surface of the skin, and continuously release to decompose odor and keep the clean taste last longer; the active agent establishes the skin micro-ecological balance, inhibits the odor-producing bacteria, maintains the skin beneficial microorganisms, regulates the skin's immunity, effectively resists oxidation, reduces the oxidation and taste reversion of sebum secreted by sweat glands, and is safe and reliable, free of toxic or side effects, easy to use and remarkable in curative effect on treating and removing body odor.