To surely assist training of the throwing form by installing a video camera in a position closer to the direction of the approach than the middle of the longitudinal direction of the lane or a position off to the right or the left of the middle of the lane width or installing them for each lane or a set of plural lanes.

A throwing form camera (video camera) 1 is equipped on a position nearer to the approach direction than the center in the longitudinal direction of a lane or a position shifted from the center in the lateral direction of the lane to right or left in the approach in every one or plural lanes. Thereby, a bowler is photographed from not the just front side or the just back side, but a side direction or an obliquely front or back direction to make the bowler easily grasp the condition when the throwing form of the bowler is played back. The throwing form of a bowler throwing on each lane is photographed from almost a constant direction to enable to uniformly provide a service on playing back a throwing form regardless of lanes.