The invention relates to the technical field of rebar production and machining, and discloses a groove optimization method of a rebar of specification of phi 14 mm. The method comprises the followingmethod of 1), preparation work; 2), rough machining; 3), middle machining; and 4), finish machining. According to the groove optimization method of the rebar of the specification of phi 14 mm, an existing eighteen rolling mills are adjusted to be seventeen rolling mills through the above mentioned steps, so that the requirement for energy sources is reduced, and then a large amount of energy is saved; through a rough rolling unit, a middle rolling unit and a finishing rolling unit, the same roller diameter is adopted, so that the vibration of the rebar in the rolling process is conveniently reduced, and the stability of the rebar in the rolling process is improved; and by reducing the rolling speed of rollers in the rough rolling unit, the medium rolling unit and the finish rolling unit, the stress surface of the reinforcing rebar in the rolling process is more uniform, so that the final quality of a product is ensured, the quality of the product is prevented from fluctuating, and thepurposes of good stability, outstanding quality of the finished product and energy conservation are achieved.