Drm method and drm system using trusted platform module

A DRM(Digital Right Management) method and a DRM system are provided to prevent important data of the data from being exposed by using a TPM(Trusted Platform Module). A term of validity is transmitted from a server(S110). A public key including the information about the term of validity is generated by using a TPM(S120). The generated public key is transmitted to the server(S130). The encrypted digital content is received from the server(S140). The received digital content is decoded by using the TPM(S150).