The invention provides a preparation method of a graphene oxide / attapulgite magnetic composite material for removing propranolol in a water body. Graphene oxide is prepared by utilizing an improved Hummers method, and then a composite material is prepared by mixing and reaction with attapulgite. The prepared composite material is taken as an adsorbent, propranolol is taken as an adsorption object,and experimental results show that the composite material has efficient adsorption and removal effects; compared with single graphene oxide, the composite material is low in production cost, and theused attapulgite is cheap and easy to obtain. The composite material applied to treat the propranolol in the water body has the advantages of being low in price, simple to operate, high in adsorptionrate, environmentally friendly, high in stability, easy to separate and the like, and has certain practical value in industrialization. The graphene oxide / attapulgite magnetic composite material has certain practical value as an adsorbent for treating cardiovascular drugs in sewage and provides a brand-new water treatment idea in the field of water treatment.