The study found that sex determination by the LAMP method was rapid and simple, and it should prove useful in identifying victims of mass disasters. The X allele was detected in approximately 32 minutes with real-time turbid meter, and the Y allele was detected in approximately 34 minutes. Analysis time was reduced to half when using loop primers. Visual detection was also possible, as the amplified product showed white turbidity. The LAMP method amplifies DNA with high specificity, efficiency, and rapidity under isothermal conditions. It uses a DNA polymerase and a set of four specially designed primers that recognize six distinct sequences on the target DNA. This study used dental pulp samples from 32 unrelated Japanese subjects. Dental pulp samples were obtained from permanent teeth that had been stored at room temperature for 1-25 years. A set of four specially designed primers was prepared based on the database from Gene Bank in order to detect X and Y alleles of the amelogenin locus. Also, X-loopR and Y-loopF were also designed as loop primers. DNA amplification was performed using a Loopamp DNA Amplification Reagent Kit. 4 figures, 1 table, and 11 references