A biosensor manufacturing method including a sheet material forming process and a dicing process. In the sheet material forming process a sheet material with plural biosensor forming sections is formed. Each of the biosensor forming sections includes a first base plate, a second base plate stacked on the first base plate and forming a capillary between the second base plate and the leading end portion of the first base plate for sucking in sample liquid, and a hydrophilic layer formed on the second base plate at least in a region facing the capillary. In the dicing process plural biosensors are obtained by dicing the sheet material with a blade from the first base plate side at the leading end of each of the biosensor forming sections, such that the leading end of the capillary opens onto the leading end face of the first base plate and the second base plate.