A brief introduction to the morphology, flight, size, habits, diet, feathers and systematic paleontology of fossil enantiornithine birds known from the Mesozoic of China is provided. Enantiornithine birds were the dominant land birds of the Mesozoic (245–65 Myr). Although they show great morphological differences from modern birds, their diversification in many respects mimics that of the modern land bird radiation and the reasons for their extinction at the end-Cretaceous remain a mystery.