▎ 摘　　要

The great success of graphene has driven the discovery and development of new 2D nanomaterials with different optical, electrical, and thermal properties. Compared with other graphene-like 2D nanomaterials, metal-free 2D nanomaterials hold great potential in biomedical applications since they exhibit much better biocompatibility and biosafety. We give an overview of some rapidly emerging graphene-like metal-free 2D nanomaterials including black phosphorus, hexagonal boron nitride, and graphitic carbon nitride, as well as 2D organic polymer-based nanomaterials, and highlight their impressive advances for bioimaging and cancer theranostics in recent years. The challenges and some thoughts on future perspectives in this field are also addressed.