This study analyzes the anticipated economic effects arising from the introduction of the mobile virtual network operator (MVNO) system in the mobile communications service market. For the analysis, actual data (or estimated data)—such as price elasticity, the number of subscribers, traffic volume, rate, and access charge—were combined with an assumption about a competition scenario in the future market. Based on this analysis, consumer surplus, and change in the service provider's profits were estimated according to the type of policy that may be adopted for the MVNO system by the regulator. The results of the analysis indicate that consumer surplus appears to increase largely because of the reduction of the mobile service rate by the promotion of “service-based competition,” which occurs upon adoption of an MVNO policy in the mobile communication service market. Moreover, the introduction of an MVNO system into the mobile communication market seems to be socially beneficial regardless of policy type if access charges are set reasonably by a cost-plus or retail-minus method. In particular, in order to make sense of the introduction of a special MVNO, whether by the cost-plus method or the retail-minus method, the correct discount rate must be used in setting an access charge between the special MVNO and the significant market power (SMP) mobile network operator (MNO).