A vertical lifting device and method are provided. The vertical lifting device includes a fixed frame fixed to a foundation. A first cavity allowing passage of a lifting rope is provided in the middle of the fixed frame. A sliding frame moving horizontally on the fixed frame is arranged above the fixed frame. A second cavity allowing passage of the lifting rope is provided in the middle of the sliding frame. At least two stepping vehicles alternately lowering or lifting weights are arranged on the sliding frame and move on the sliding frame. The stepping vehicles are spaced in preset distances. The lifting rope penetrates through the stepping vehicles in sequence. Each stepping vehicle is provided with a clamping part clamping the lifting rope and a driving mechanism driving the stepping vehicle to move on the sliding frame.