Abstract: Due to the merits of saving communication resources and reducing control energies, event-triggered consensus control of multi-agent systems has gained significant attention. In this paper, the basic framework and key issues of event-triggered consensus control are firstly introduced, then the state-of-the-art is comprehensively reviewed with detailed discussions on the advantages and disadvantages of various triggering conditions. Besides, the application of adaptive technique to event-triggered consensus control is also clarified. Finally, some open issues which are worthy of further investigation are provided.