Resource allocation of 5G cellular network slicing has been gaining huge interest recently. However, it is not well-explored under the Multi-tenant and Multi-service Coexistence Network scenario. This paper proposes a dynamic network slicing scheme for the 5G Coexistence Network, which considers tenants, priority, baseband resources, slice granularity, service characteristics, quality of service (QoS), and fairness index. The framework of the network slicing scheme consists of a group-level, which performs clustering preprocessing, setting the priority of service, and filtering the desired characteristic service groups; and a slice-level, which performs radio resource allocation among services and follows the changes in the network environment closely. The simulation results show that the proposed scheme can achieve higher goal service group QoS, fairness, and overall QoS compared with three kinds of baseline schemes.