A novel DNA analysis method suitable for terminal medical facilities has been developed using a microchannel device, which allows high accuracy DNA detection simple operation. Our method does not require immobilization of probe or sample DNA; solutions are simply injected into the microchannel, and all the reactions are performed in the liquid phase. The coefficient of variation of sequence-selective DNA detection was ca. 5%. The method will also make it be applicable to various sequences. These features make it suitable for use in medical examination sites and terminal medical facilities.