There is provided a plate (10) on which a channel pattern (110) is formed, which channel pattern includes a first channel (116) into which a buffer agent is injected, and a second channel (117) having, in a portion thereof, a quantification part (117a) that has a portion common to the first channel and holds a predetermined amount of a biological sample, the biological sample being injected into the channel including the quantification part, and the plate (10) is rotated at a high speed by a filling unit (20) to fill the buffer agent in the first channel, and thereafter, the second channel is pressurized by a discrimination unit (30) to fill the biological sample in the second channel, and simultaneously, a predetermined amount of the biological sample is added into the buffer agent. Therefore, when performing discrimination of the biological sample, a discrimination result can be obtained accurately in a short time without the necessity of complicated preparation works.