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New Delhi metallo-β-lactamase (NDM) is a series of enzyme conferring resistance to β-lactam antibiotics including the carbapenems. The bla NDM gene has been reported in a variety of Gram-negative bacilli, especially in the Entero bacteriaceae and Acinetobacter spp., which is deeply disconcerting for public health worldwide. In this study, recombinase polymerase amplification assays using a basic detection (Basic-RPA) and a real-time fluorescent detection (Exo-RPA) were established for detecting bla NDM gene. The RPA reactions were performed at 39 °C and finished within 20 min. Using different copy numbers of pMD18T-NDM plasmid DNA as templates, we identified the detection limit of Basic-RPA assay (1.85 × 103 copies/μL), conventional PCR assay (1.85 × 104 copies/μL), Exo-RPA assay (1.85 × 102 copies/μL) and real-time PCR assay (1.85 × 102 copies/μL). Both Basic-RPA and Exo-RPA assays were highly specific for detecting bla NDM , as there were no cross-reactions with the strains without bla NDM gene. Examination of 62 clinical samples by RPA assays and PCR assays showed the same results, suggesting that RPA assays are reliable in clinical diagnosis. The amplification time of RPA is much shorter than that of other molecular techniques, it is easy to implement and has the potential for clinical application. Note: Recombinase polymerase amplification assays using a basic detection (Basic-RPA) and a real-time fluorescent detection (Exo-RPA) were established for bla NDM gene. The RPA reaction was performed at 39 °C, and the results were obtained within 20 min. The analytical sensitivity of the RPA assay was tested, using a 10-fold serial dilution of plasmid pMD18T-NDM DNA. The results showed that RPA had high sensitivity. Both Basic-RPA and Exo-RPA assays were highly specific for the detection of bla NDM. Unlabelled Image • Exo-RPA and Basic-RPA assays were developed and evaluated for rapid detection of bla NDM gene. • The Exo-RPA assay was highly specific and sensitive. • The Exo-RPA and Basic-RPA assays were as sensitive as conventional PCR and real-time PCR on clinical sample detection. [ABSTRACT FROM AUTHOR]