The application provides a WOSA-based operation method and operation device for financial self-service equipment. The method comprises the following steps: obtaining an operation request for the financial self-service equipment; calling a target middleware interface corresponding to the operation request, and performing a process of responding to the operation request, wherein the target middleware interface is an interface obtained by encapsulating each of the atomic interfaces conforming to the WOSA financial service extension specification for responding to the operation request, the process of responding to the operation request comprises the following steps: calling an atomic driver service program of the financial self-service equipment according to the WOSA financial service extension specification so as to perform the operation corresponding to the operation request; obtaining a return value obtained after the operation corresponding to the operation request is performed, and returning the return value to an upper application. In the application, the development process can be simplified and the development efficiency can be improved by the above method.