For cellular downlink transmissions, we propose an approach leveraging cooperative device‐to‐device (D2D) communications and network coding (NC), which can substantially reduce the cellular resource consumption and the total energy consumption. In the proposed approach, the base station generates and broadcasts linear combinations based on the packets requested by different user equipments (UEs) until at least one UE can recover all the original packets, called mature UE. Then, a selected mature UE broadcasts new linear combinations based on the recovered original packets to neighbors via D2D until all UEs can decode their packets. A semi‐centralized cooperative control method is proposed for cellular uplink transmissions, where UE relays are randomly selected according to a certain density decided by the base station. Two specific cooperative approaches, i.e. the random UE relay approach and the NC approach, are proposed for D2D communications.