Loop-mediated isothermal amplification (LAMP), that amplifies DNA with high specificity, efficiency and rapidity under isothermal conditions have been developed by Notomi et al (Nucleic Acids Res.28, 2000). This method employs a DNA polymerase and a set of four specially designed primers that recognize total of six distinct sequences on the target DNA. An inner primer containing sequences of the sense and antisense strands of the target DNA initiates LAMP. In the present investigation, we evaluated the usefulness of LAMP for the rapid identification and sensitive detection of Mycobacterium avium subsp. paratubeculosis (MAP). The primers for LAMP were designed to amplify the gene sequence of IS900, HspX, dnaJ and F57 fragments of MAP. DNA templates were prepared from the cultured bacterial suspension of MAP strain ATCC 19698. Amplification and detection of the genes to be amplified was completed in a single step, by incubating the mixture of gene sample, primers, DNA polymerase with strand displacement activity and substrates at a constant temperature (in the region of 65ºC). The amount of DNA fragments synthesized was assayed by gel electrophoresis and by real-time monitoring of the turbidity produced by white precipitate of magnesium pyrophosphate in the reaction mixture. As a result, two gene fragments of IS900 and HspX were effectively amplified by LAMP test, but other two gene fragments of dnaJ and F57 were not. Two MAP strains yielded positive results, but other bacterial strains including M. avium subsp. avium yielded negative results in the tests for IS900. The concentration of DNA templates of MAP amplified by LAMP test was 0.01 pg/ul in the case of IS900. The LAMP test had a sensitivity equal to or greater than that obtained by traditional PCR techniques and were much more rapid, taking only two hours compared with 4 hours for PCR test. These results show that LAMP test might have a potential usefulness as a rapid and sensitive method to detect MAP in faeces or tissues of animals infected with MAP.