To cope with data communication explosion, the alternative, “D2D communication” which enables mobile devices to communicate each other without base station is studied. D2D providing service at a lower cost than cellular network is advantageous for user and also helpful when infra system is out of order by natural disaster. Even if D2D communication has a lot of benefits, that the D2D communication interferes cellular links as well as D2D link each other should be managed. This paper proposes a radio resource allocation policy for D2D link. Firstly, in frequency domain, by introducing D2D belt concept (the area where users cannot user frequency available only for D2D link) orthogonality between cellular links and D2D links is guaranteed in frequency domain. Secondly, by allocating un-overlapping subframe to D2D links, the interferences between D2D links can be eliminated.