The invention discloses a method for heating and upsetting of the end of a steel bar. The method includes the steps that 1, the steel bar is heated, specifically, a first heating electrode and a second heating electrode are arranged at the end of the steel bar, and acting force is applied to the first heating electrode and the second heating electrode correspondingly, so that the plane of the first heating electrode is tightly attached to the end face of the end of the steel bar and the second heating electrode is tightly attached to the outer surface of the steel bar; the first heating electrode and the second heating electrode are started to heat the steel bar continuously; 2, the steel bar is subjected to heat preservation, specifically, the first heating electrode is moved from the end, and the temperature is uniform after heat preservation is conducted for a period of time; and 3, the end of the steel bar is subjected to upsetting, specifically, upsetting force is applied to the end of the steel bar through the plane of the first heating electrode in the length direction of the steel bar, the end of the steel bar is pushed to deform and move in the length direction, and the end is pushed into an upsetting clamp to form an expanded upset end. The method for heating and upsetting of the end of the steel bar has the advantages that the anchoring rigidity is high, performance is excellent, machining is fast, the quality is stable, and installation and construction are convenient; and the construction quality of concrete at the joint positions can be ensured, and relevant performance of a reinforced concrete structure is improved.