The utility model relates to a single-pile type steel cylindrical foundation. The utility model aims to provide a single-pile type steel cylindrical foundation which is simple in structure, convenientto construct, low in cost, safe and reliable. The technical scheme of the utility model is as follows: the nursing bed comprises a bed body, the utility model discloses a single-pile type steel cylindrical foundation. The method is characterized in that the method is characterized by comprising the following steps; wherein the large-diameter thin-wall steel cylinder, the steel top plate, the arcsteel cylinder and the cylinder are sequentially and coaxially connected from bottom to top. Wherein the large-diameter thin-wall steel cylinder is vertically fixed on a seabed; wherein a steel top plate is fixed at the top end of the large-diameter thin-wall steel cylinder and is blocked by the steel top plate, the outer diameter of the lower end of the arc steel cylinder is matched with the steel top plate, the outer diameter of the upper end of the arc steel cylinder is matched with the cylinder, the outer diameter of the arc steel cylinder is gradually reduced from the lower end to the upper end, and a connecting flange is arranged at the top end of the cylinder. The utility model is applicable to the technical field of civil engineering in wind power generation industry.