The invention discloses a six-blade differential speed pump driven by Pascal non-circular gears. The conventional differential speed pump has the problems of difficulty in pressure pulsation optimization, liquid trapping and the like. Both a first Pascal non-circular gear and a second Pascal non-circular gear of the six-blade differential speed pump are fixed with an input shaft; both a first conjugate Pascal non-circular gear and a first impeller are fixed with an output shaft; the first conjugate Pascal non-circular gear is engaged with the first Pascal non-circular gear; a second conjugate Pascal non-circular gear and a second impeller are fixedly connected with a shaft sleeve; the shaft sleeve is moveably sleeved upon the output shaft; a first liquid discharging port, a first liquid suction port, a second liquid discharging port, a second liquid suction port, a third liquid discharging port and a third liquid suction port are formed in a pump shell along the circumferential direction in sequence; both the first impeller and the second impeller are provided with three blades; a one-way pressure relief valve is arranged in each of the blades. The six-blade differential speed pump driven by the Pascal non-circular gears has large displacement and stable flow; a non-uniform speed law is easy to adjust; and the problem of liquid trapping is solved effectively.