The utility model provides a power transmission ground wire falling-prevention wire clamp comprising an outer clamp body and an inner clamp body. The outer clamp body is provided with an outer clamping groove with a lateral opening and the inner clamp body is provided with an inner clamping groove with a lateral opening. The outer clamp body is provided with an installing groove. The inner clamp body is installed on the outer clamp body through the installing groove. A power transmission ground wire passes through the outer clamping groove and the inner clamping groove. An elastic pressing device is arranged between the outer clamp body and an inner clamp body. The elastic pressing device drives the outer clamp body and the inner clamp body to move oppositely to clamp the power transmission ground wire. The outer clamp body and the inner clamp body are connected in a mutually rotatable manner. During rotation, a clamping part is formed between the outer clamp body and the inner clamp body and can clamp a wire. Under the action of the elastic pressing device, a certain force is formed between the inner clamp body and the outer clamp body and thus the outer clamp body and the inner clamp body can be pulled tightly thereby.