Persistent luminescent nanoparticles (PLNPs) are a kind of nanomaterials which can continue to emit light after stopping external excitation. This unique optical property of PLNPs allows their application in luminescence detection without constant external excitation. Moreover, it can reluminesce under the excitation of appropriate near-infrared light (NIR). This excellent optical property enables it to detect persistent luminescence without in-situ continuous excitation, so as to avoid the interference of self-fluorescence and scattered light from organisms and tissues, thus significantly improving the sensitivity of biological analysis. In order to make full use of the advantages of PLNPs in biological applications, it is becoming more and more important to design PLNPs-based nanoprobes and general strategies for connecting PLNPs with bioactive molecules / biomarkers. The use of FRET system is the most suitable strategy for the preparation of PLNPs-based nanoprobes, which solves the problem of high background signal in traditional fluorescence sensing. In this review, we summarize the synthesis methods of PLNPs and systematically introduce the research progress of PLNPs in biomedicine and food contamination detection, focusing on the application of PLNPs in bioimaging and biosensing. The research direction of PLNPs nanoprobes in the diagnosis and treatment of tumors was prospected.