We present a model based on utility functions for radio resource allocation (RRA) in multimedia DS-CDMA systems.We proposed two utility-based RRA algorithm,URRA-EF (Utility-based Radio Resource Allocation-Efficiency Focused) and URRA-UF (Utility-based Radio Resource Allocation-User Focused).The goal of URRA-UF is to achieve the resource optimization which maximizes the system overall utilities,while URRA-UF has its advantages on providing fairness to users.To avoid high computational complexity of solving nonlinear optimization problems,we reformulate the utility-based RRA problem as a market model so that the optimal resource allocation can be achieved in a distributed manner.Simulation results show that our algorithm is flexible and efficient for mobile multimedia DS-CDMA systems,and the improvement of performance is significant.