The invention provides an ice-resistant cone structure for an offshore wind power foundation and a construction method. The ice-resistant cone structure for the offshore wind power foundation comprises a single-pile body, a negative-pressure barrel, a platform and an ice-resistant cone. The negative-pressure barrel is arranged on the single-pile body in grouting connection. The upper surface of the negative-pressure barrel is not higher than the seabed surface. The platform is arranged on the upper portion of the single-pile body and fixedly connected with the single-pile body. The platform ishigher than the sea level. The single-pile body is sleeved with the ice-resistant cone. The upper end of the ice-resistant cone is connected with the platform through a first traction piece, and thelower end of the ice-resistant cone is connected with the negative-pressure barrel through a second traction piece. The height of the ice-resistant cone is matched with the sea level. The negative-pressure barrel is arranged on the sea mud surface, the platform is arranged above the sea level, and an installation foundation is provided for installation of the ice-resistant cone so that the ice-resistant cone can be stably connected with the single-pile body in a suspension traction manner. The installation manner is simple and convenient, and the ice-resistant cone can be installed without grouting.