A square baler includes a frame, a bale chamber formed on the frame, a knotting part having a knotting member and a needle member, wherein the knotting member is provided to knot and cut a bale string, and the needle member is provided to perform a vertical angular movement and guide the bale string to the knotting member, a pickup part picking up and providing hay in a front inner space of the bale chamber, and a rake part rotatably installed so as to, during the rotation and downward motion of the rake part, push and compress the hay, which was picked up and provided to the inner space of the bale chamber, towards the rear side.