Abstract: A ball feeder for ball serving machine includes a seat consisting of a hollow transfer frame and a shaft bear, a rotating unit mounted to one side of the seat and having a ball scoop extended from an end thereof, and a plurality of guide sections sequentially rotatably connected at an end to the shaft bearing. The guide sections may be turned about the shaft bearing in the same direction to form a nonlinearly inclined spiral ball guide path. A ball put in the top guide section automatically rolls down along the ball guide path and falls into the transfer frame to be caught by the ball scoop. When the ball scoop is turned by the rotating unit to face downward, the ball on the ball scoop falls into a feeding mouth on a body of the ball serving machine and is automatically served.