A service providing method in a satellite communication system includes: receiving service request signals from terminals which exist in a service area and are to receive the communication service; calculating the total traffic volume within the service area by using the service request signals; forming hierarchical multi beams which cover the calculated traffic volume to provide a service to the terminals; and allocating resources and power to the formed hierarchical multi beams, transmitting the resource and power allocation information to the terminals through control channels, and providing the service to the terminals through the formed hierarchical multi beams by using the allocated resources and power.