Provided is a device and method for scheduling uplink resources in a wireless communication system supporting VoIP . When its data rate is decreased, an MS notifies a BS of the rate decreased. When increasing its data rate, the MS requests resource allocation to the BS by transmitting a BR header or a CQICH codeword. Compared to the conventional ertPS in which the BS periodically allocates uplink resources to the MS irrespective of the state of the MS, the BS does not allocate uplink resources when the MS transitions form a talk-spurt period to a silence period. Therefore, resources consumption arising from unnecessary bandwidth allocation is reduced.