The invention discloses a veterinary compound levamisole hydrochloride suspension oral liquid and a preparation method thereof. The compound levamisole hydrochloride suspension oral liquid is composed of levamisole hydrochloride, oxyclozanide, cobalt sulfate, agar powder, a suspending aid, a wetting agent, disodium ethylene diamine tetraacetate and a surfactant. A stable and uniform dispersion system is formed under the action of mechanical shearing force by wetting with the wetting agent and using the dispersion characteristic of the surfactant and the suspension aiding characteristic of the suspending aid on the basis of levamisole hydrochloride and oxyclozanide in order to prepare the compound suspension oral liquid, and the oral liquid is taken by cattle and sheep in a feed mixing or drinking water mixing mode to dispel parasites in order to treat and prevent infection of gastrointestinal nematodes, lung nematodes and other parasites in clinics and animal production, and can improve the stress resistance and the immunity of animals.