The invention provides a multifunctional valve key assembly, and belongs to the technical field of auxiliary equipment. The multifunctional valve key assembly comprises a key body, first assembly holes or second assembly holes, and first handle sleeve holes or second handle sleeve holes, wherein the key body is integrally formed through casting, the first assembly holes or the second assembly holes are formed in the middle of one unlocking face of the key body, and the first handle sleeve holes or the second handle sleeve holes are formed in the two sides of the first assembly holes or the second assembly holes; and the first assembly holes are connected with magnetic unlocking pieces in a threaded mode, and magnetic columns are embedded in the second assembly holes or special-shaped mechanical unlocking pieces or magnetic unlocking pieces are connected into the second assembly holes in a threaded mode. According to the multifunctional valve key assembly, two unlocking faces are included and arranged in different ways so that at least two types of different lock valves can be unlocked, and the adaptability is higher; all the unlocking pieces are embedded or connected in the threaded mode, and thus the multifunctional valve key assembly can be carried by a worker conveniently through hanging piece holes; in addition, the technique for integrally forming the key body through casting is simple, only one die is needed, and the production cost is low; and meanwhile, one key can correspond to multiple lock valves, and thus raw materials used for manufacturing the key are saved.