The invention relates to an anthelmintic drug for livestock, and particularly relates to a preparation method of albendazole / ivermectin powder for livestock, which is convenient to use and remarkable in drug effect. The preparation method comprises the following steps: stirring and mixing 0.1-0.2 part of ivermectin and 2-4 parts of sodium carboxymethyl cellulose, adding 2-4 parts of flavoring agent after the powder is evenly mixed, and further evenly mixing; stirring and mixing 5-15 parts of albendazole and 10-20 parts of sodium chloride, adding 5-10 parts of sodium citrate after the powder is evenly mixed, and further evenly mixing; and then, adding the former into the latter through an equivalent increment method, evenly stirring, adding the balance of other auxiliary material, further evenly stirring and mixing, and subpackaging to obtain the finished product, wherein the other auxiliary material is soluble starch or microcrystalline cellulose. The drug provided by the invention is a dry suspension, can be proportionally added in a drinking fountain directly for use, and facilitates the all-round dosing in a large-size livestock farm; the drug avoids the toxic and side effect caused by uneven feed mixing and is more convenient to use; and the drug effect is remarkably enhanced, and the cost is obviously lowered in comparison with the prior art, thereby ensuring that the drug has wide application prospects.