The invention discloses an automation stamping production line and a workpiece auxiliary rotary mechanism thereof; the workpiece auxiliary rotary mechanism comprises a fixed plate arranged on a lower die, a support material rack supporting workpieces, and a power element driving the support material rack to move in a die opening direction; one end of the power element is fixed on the fixed plate, the other end of the power element is fixed on the support material rack, and the power element drive the support material rack to move close to the fixed plate or move away from the fixed plate; the support material rack is provided with an avoid port, and a die work mold surface penetrates the avoid port. The workpiece auxiliary rotary mechanism can realize automatic overturn of the workpiece in a punching process, thus reducing design requirements of a manipulator, reducing production cost, and improving work efficiency.