PURPOSE: To eliminate the clogging of a generator part by providing an automatic valve between the powder entering part of the casing of a powder-liquid mixing and dispersing machine and a powder supply port, and cyclically opening and closing the same to effectively mix and disperse a polymeric powder and a liquid.

CONSTITUTION: A suction chamber casing 8 demarcating a suction chamber 10 having an orifice 8a on the axial line of the output shaft 2 thereof and equipped with a liquid suction port 9 crossing the axial line at a right angle is attached to a dispersing chamber casing 5. A suction cover 11 equipped with a powder suction port 12 is attached to the suction chamber casing 10 on the side opposite to a motor and the powder supply port 15 of a powder hopper 14 is connected to the suction chamber casing 10 through an automatic valve l3, and the automatic valve 13 is cyclically opened and closed by a timer or a sequencer. By this constitution, since suction capacity is enhanced and a liquid is sufficiently sucked, the clogged liquid is carried away.