A security management method in multimedia middleware of a terminal that can download a multimedia service provided from an external entity, the method comprising: if there is an access request for a particular multimedia service, determining whether there is a corresponding multimedia service; if the access-requested multimedia service does not exist in middleware of the terminal, performing negotiation for secure session setup with the external entity; setting up a secure session to the external entity using a security parameter selected as a result of the negotiation; and receiving information for the download from the external entity through the secure session, and determining whether to execute the download, wherein the information for the download comprises a service profile comprising requirements for installation and execution of the multimedia service, and wherein the determination of whether to execute the download further comprises: checking a target profile referring to information on an execution environment of the corresponding multimedia service by comparing the target profile with the service profile; checking a security profile referring to security information related to the negotiated secure session by determining whether said security information is valid; determining to download the multimedia service based on the checking steps; and downloading the multimedia service through the secure session, wherein the security parameter comprises a list of protocols/algorithms supported by the multimedia middleware. if there is an access request for a particular multimedia service, determining whether there is a corresponding multimedia service; if the access-requested multimedia service does not exist in middleware of the terminal, performing negotiation for secure session setup with the external entity; setting up a secure session to the external entity using a security parameter selected as a result of the negotiation; and receiving information for the download from the external entity through the secure session, and determining whether to execute the download, wherein the information for the download comprises a service profile comprising requirements for installation and execution of the multimedia service, and wherein the determination of whether to execute the download further comprises: checking a target profile referring to information on an execution environment of the corresponding multimedia service by comparing the target profile with the service profile; checking a security profile referring to security information related to the negotiated secure session by determining whether said security information is valid; determining to download the multimedia service based on the checking steps; and downloading the multimedia service through the secure session, checking a target profile referring to information on an execution environment of the corresponding multimedia service by comparing the target profile with the service profile; checking a security profile referring to security information related to the negotiated secure session by determining whether said security information is valid; determining to download the multimedia service based on the checking steps; and downloading the multimedia service through the secure session, wherein the security parameter comprises a list of protocols/algorithms supported by the multimedia middleware.