The present invention relates to a resource allocation requesting method and a packet scheduling method for uplink packet traffic in a mobile communication system, and an apparatus of the packet scheduling method. For efficient scheduling for the uplink traffic, scheduling is performed according to characteristics of traffic between a base station and user equipment (UE). Particularly, when the traffic generates a variable size packet on a periodic basis, the traffic is classified into first traffic that generates a completely variable size packet on a periodic basis and second traffic that generates a quasi-variable size packet on a periodic basis. In addition, the UE requests resource allocation in a different form from the base station depending on the type of traffic, and the base station performs scheduling according to the resource allocation request. Therefore, the UE requests resource allocation in accordance with traffic characteristics and the base station performs scheduling according to the traffic characteristics so that optimal uplink scheduling can be performed.