Improved breast pump

An improved breast pump comprises a feeding bottle, a connection pipe part and a suction cup which are sequentially connected. The upper end of the feeding bottle is connected with the lower end of the connection pipe part. A suction cup pipe is arranged on the lateral side of the connection pipe part. The tail end of the suction cup pipe is connected with the suction cup. A negative pressure cavity is formed in the upper portion of the connection pipe part and comprises a cavity formed in the connection pipe part, a membrane arranged in the cavity, and a negative pressure cover piece. A transition cavity similarly in a semicircular shape is formed in the lower portion of the negative pressure cavity. The lateral side of the transition cavity is connected with the suction cup pipe. The bottom of the transition cavity is connected with a one-way valve. An outer suction hole is formed in the upper portion of the negative pressure cover piece. The transition cavity similarly in the semicircular shape is formed in the lower portion of the negative pressure cavity, and therefore bubbles of milk sprayed out under the negative pressure can be eliminated in the transition cavity, milk can rapidly flow into the feeding bottle, milk bubbling is greatly reduced, the negative pressure suction frequency is increased by decreasing the length of an air way, the milk sucking efficiency is improved, and the improved breast pump has the advantages of being convenient to use and capable of rapidly sucking out milk.