ObjectiveTo develop a new method for rapid detection of canine distemper virus by reverse transcriptase loop-mediated isothermal amplification method (RT-LAMP). MethodAccording to the published GenBank sequence, four strips of primers specific recognizing NP gene of canine distemper virus were designed. We studied the optimal reaction conditions, specificity, sensitivity, and its visualized judging method of products. Then we used 63 clinical specimens to verify its efficiency in field detection. ResultsThe amplication can be performed at a constant temperature 60℃ within 1 hour. Specific primers did not recognize genes of other virus commonly infecting canine. The results of RT-LAMP could be easily observed by naked eyes after SYBR green I staining. In 63 specimens collected from Nanjing and Shangdong, 45 samples(71.4%)were positive, but only 40 samples (63.5%) were positive using RT-PCR. Conclusion The results of our study demonstrate a higher superiority of specificity, sensitivity, efficiency and convenience of the RT-LAMP method, and provide a new detection method for canine distemper virus.