To meet the growing demand for traffic

ultra-dense network is one of the key technologies for the 5 Gnetwork.In recent years

the number of users and services increase rapidly in the ultra-dense network composed of Long Term Evolution（LTE）small base stations.The paper proposes an access control algorithm based on the cross-layer effective capacity

which can ensure the Quality of Service（QoS）of users and increase the throughput of the network.The algorithm considers the QoS requirements and the channel condition.It also defines the selection factor to determine the accessed LTE small base station.Therefore

load balance can be realized in each LTE small base station resulting in maximum effective capacity of ultra-dense network on the basis of ensuring the QoS of users.The simulation results show that compared with the traditional algorithm

the algorithm proposed in this paper can improve the system capacity significantly while guaranteeing the users’ QoS.