A method for processing a request for MO data using a cache validator (CV) allocated to an MO instance according to an embodiment of the present invention, comprises the steps of: receiving uniform resource identifier (URI) information to identify the MO data of requesting certain MO data of the MO instance from a server; determining whether the URI information includes a first CV; transmitting the requested certain MO data to the server when the URI information does not include the first CV; and transmitting a second CV for the MO instance when the URI information indicates a root node of the MO instance, wherein the MO instance has a tree structure consisting of at least one node; the MO data comprises the name, value and structure of a node included in the MO instance, and the method is performed by a terminal.