A stirring mixer for a dental impression material to decrease bubbles to be generated in a mixed dental impression material and the material to be left in a tubular main body, the mixer has a tubular main body wherein a discharging portion is provided following the mixing portion via a throttling portion from an injecting portion to which two pastes are injected, and a stirring rod with protruding stirring blades is rotated by a motor, leading ends of 1st blades are positioned in a largest diameter portion of the throttling portion, leading ends of 2nd, 3rd and 4th blades are positioned in an inner diameter portion of the mixing portion, 1st blade in a rotational direction and interval between 3rd and 4th blades is wider than that between the other adjacent blades, and opposing faces of 3rd and 4th blade to each other bulge towards the other blades.