Bacterial infection is an acute infection caused by pathogens or conditional pathogens, which leads to severe disease and even death. It has become a significant reason for diseases and deaths worldwide. Therefore, rapid and precise detection, diagnosis, and treatment in the early stage are the key to deal with bacterial infections. Over recent years, along with the advances in biomaterials and nanotechnology, numerous nanomaterial-based multifunctional probes have been extensively explored in the biomedical field. Because of their excellent optical properties, inorganic optical nanoprobes are used to rapidly detect bacterial infection in the early stage and show excellent antibacterial properties, which has a great application prospect in antibacterial therapy expected to reduce the risk of bacterial infection. In this mini-review, we generally overviewed and summarized recent progress on inorganic nanoparticle-based optical imaging techniques as a platform to construct functional theranostics for the efficient treatment of bacterial infections. The opportunities and challenges in the application of fluorescent optical nanoprobes are prospected.