<p>Saucrosmylidae as an enigmatic Mesozoic lineage of Neuroptera, is characterized by its large body, typically expanded RA area, dense crossvenation and diversified wing patterns. A new species of Saucrosmylidae, namely <i>Huiyingosmylus wangi</i> sp. nov. is described based on a well-preserved specimen. This specimen bears four stretched wings and a partial body, including a significantly shortened foreleg, and was collected from the Middle Jurassic of Daohugou, Inner Mongolia, China. This new species further enhances the species diversity of Saucromylidae and also provides new information on the biological characteristics of this family.</p>