(1) According to the use of carbon steel can be divided into carbon structural steel, carbon tool steel and free cutting structural steel three, carbon structural steel is divided into engineering construction steel and free cutting structural steel two;

(2) According to the smelting method can be divided into open-hearth steel, converter steel;

(3) According to the deoxidation method can be divided into boiling steel (F), killed steel (Z), semi-killed steel (b) and special killed steel (TZ);

(4) carbon steel according to carbon content can be divided into low carbon steel (WC 0.25% or less), medium carbon steel (WC0.25%0.6%) and high carbon steel (WC > 0.6%);

(5) According to the quality of steel, carbon steel can be divided into ordinary carbon steel (phosphorus, sulfur is higher), high-quality carbon steel (phosphorus, sulfur is lower) and high-quality steel (phosphorus, sulfur is lower) and ultra-high quality steel.