Aims: To develop a rapid and sensitive method for detecting Brucella spp. Methods and Results: Two sets of six Brucella-specific primers for loop-mediated isothermal amplification (LAMP) were designed from the sequence of the Brucella abortus BCSP31 gene. The specificity and sensitivity were examined for six Brucella species (22 strains) and 18 non-Brucella species (28 strains). The LAMP assay was specific to Brucella spp. in 35 min at 63 degrees C and sensitive (detected 10 fg of genomic DNA). The assay was also applied for the detection of Brucella DNA in contaminated milk and infected mouse organs. Conclusions: We developed a sensitive and specific LAMP assay for Brucella spp., with the test appearing to be useful for the detection of the pathogen from clinical and food samples. Significance and Impact of the Study: This is the first report of the development of LAMP for the detection of Brucella spp. As the LAMP assay can be performed at a constant temperature and its reactivity is directly observed with the naked eye without electrophoresis, our assay should be useful for the diagnosis of brucellosis as well as the detection of the bacteria in environmental or food samples.