Abstract: Bamboo-shaped cracking occurred when the GCr15 steel continuous casting billet was rolled, the causes of billet cracking were analyzed by chemical composition analysis, fracture macroscopic analysis, metallographic examination, crack location of bamboo-shaped cracking steel billet measurement. The results show that the GCr15 steel billet was heated too fast and the thermal stress was too high at the beginning of heating, which led to the cracking of steel billet. Due to the large temperature difference at the location of the water cooled beam, the steel billet more easily cracked, which eventually led to the bamboo-shaped cracking of the GCr15 steel billet.