The aim of this paper is to propose a metadata-net as ontology to make a relation with similar metadata by analyzing structure and semantics of multimedia content metadata. Also, it is to suggest a multimedia contents management system based on a metadata-net (M²SM) as a methodology to provide integrated services for managing and searching various multimedia contents created and stored in home network-accessible consumer electronics (CEs). The proposed system helps users, who use a mobile device outside home, search and view highly relevant multimedia contents. When user wants to search some multimedia contents by metadata, M²SM provides query extension and modification and restriction using metadata-net in order to reduce increasing searching time caused by traversing unnecessary CEs in home network. The proposed system was implemented on a home server that acts as a gateway for establishing connections between home network and Internet. It supports various standards about home network and controls CEs to manage and search multimedia contents. In this way, M²SM reduces the search results delivered to mobile devices from home network, so power efficiency of mobile devices increase because CPU and network usage are declined.