Abstract: A system for automatically dispensing stock solutions is disclosed, comprising a dispenser, pipette keeping and washing units and a control unit. The respective pipette keeping and washing units have different types of pipettes. First, the control unit selects the most appropriate pipette according to the type and amount of mixture of stock solutions to be prepared. The dispenser then receives the selected pipette from the corresponding pipette keeping and washing unit and is detachably fitted with the appropriate pipette to feed a predetermined amount of stock solution into a receptacle by manipulating the pipette. Having finished dispensing, the dispenser transfers the used pipette back to the corresponding pipette keeping and washing unit. On completion of the transfer, the control unit causes the pipette keeping and washing unit to wash the transferred pipette.