NanoFCM (Flow NanoAnalyzer) allows the multi-parameter testing of various biological nanoparticles, such as exosomes, virus, bacteria, particles with subcellular structure, providing high resolution flow analysis techniques for nanoparticles. By characterizing the size, concentration and biochemical properties of single nanoparticles (7-1000 nm) with high-definition, high-selectivity and high-throughput, the Flow NanoAnalyzer offers a powerful tool for life science research and the development of the nanomedicine industry. NanoFCM can achieve direct characterization of single lentiviruses. In addition to the analysis of particle size distribution and concentration, the precise analysis of various structural components (VSV-G, p24, genome, capsid, capsule etc.) is also possible, providing a comprehensive analysis of lentivirus samples (Table 1). NanoFCM provides a rapid solution for attaining information about lentivirus titer, purity and empty/full ratio, and is of great value during various stages of application, such as research and development, production, purification, quality control, stability assessment and etc.