To shorten the stirring time for a dispenser.

The residual quantity of a sample is calculated by a sample residual quantity calculation part 3, based on liquid level positional information detected by a liquid level detection part 1 and on bottom dead point information of a sample container previously stored, and then is sent to a suction quantity and stirring frequency calculation part 5. Suction quantity and suction/discharge frequency, appropriate to the residual quantity of the sample at stirring the sample, are calculated by the suction quantity and stirring frequency calculation part 5. When the residual quantity of the sample is small, the suction/discharge quantity is reduced to suppress the suction of air into a dispensing system, and also the stirring frequency is reduced. When the residual quantity of the sample is large, the suction/discharge quantity is increased and the stir frequency is also increased. A stirring control part 6 drives a pump with a pump drive mechanism 9, based on the suction quantity and the stirring frequency calculated by the suction quantity and stirring frequency calculation part 5, and then a probe is made to move vertically by a probe transfer mechanism 7 for stirring the sample.