A wave-shaped guardrail is a movable steel guardrail made of combined wave-shaped plates used at the openings of a highway median. It consists of two wave-shaped steel guardrail panels and two posts fixed between them. The posts are securely mounted between the panels. During normal highway operation, the guardrail can be conveniently inserted into pre-set insertion holes at the opening with the aid of the posts, providing isolation and protection. It complements the guardrail belt on the outside of the highway, maintaining uniformity and aesthetics. In the event of a collision with the vehicle, the wave-shaped steel guardrail panels, with their excellent impact resistance and energy-absorbing properties, are not easily damaged and offer excellent protection for the vehicle and its occupants.