The invention provides a high-strength chair. The high-strength chair comprises a seat plate and supporting frames connected with the seat plate, wherein a reinforcing ring is arranged at the bottom of the seat plate; the reinforcing ring is connected with the supporting frames; reinforcing columns are arranged on the outer sides of the supporting frames; semicircular reinforcing edges are arranged on the two sides of the supporting frames; a pedal plate is arranged between the supporting frames; and reinforcing ribs, which downward extend to the bottoms of the supporting frames, are arranged on the two sides of the pedal plate. With the adoption of the high-strength chair, the problems that a current plastic stool or chair has low strength and is easy to deform are solved; and the high-strength chair is simple and practical in structure and has an extremely great market popularization value.