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Development of a simple, fast, and safe method to detect neutralizing antibody levels to a pathogen is urgent to help understand the immune status of convalescent patients and the immune responses after vaccine. Here we report the development of a cell-free and virus-free beads-based virus neutralization assay. We focused on the detection of neutralization antibody (nAb) in blood circulation to SARS-Cov-2 spike protein receptor binding domain (RBD). This assay uses histidine tagged recombinant RBD protein to replace living virus and uses streptavidin coated polystyrene beads as a carrier of human angiotensin-converting enzyme 2 (hACE2). This bead serves as a surrogate for target cells. Neutralization was detected by the decrease or absence of fluorescence signal associated with RBD. The assay was compared to a cell-based neutralization assay and ELISA, and these results are reported. The bead-based assay is simple, fast, safe and importantly, can truly reflect the immune status of individuals. The result of the assay can help assess the response of vaccine recipients and assist in selecting serum from convalescent patients for therapeutic purposes.