Owing to its fast development, chiral nanoscience has become one of the core research topics in chemistry, physics, medicine and materials science. Recently, many efforts have been focused on constructing new types of chiral nanomaterials with unique optical activity. This themed issue highlights the state-of-the art progress in this field, based on a series of invited and selected articles published in Chemical Science. These articles cover diverse nanomaterials, including organic, inorganic, organic–inorganic hybrid and superstructured nanomaterials. The details based on the composition are as follows: