Vacuum Pressure Casting lance nozzle is composed of outer pipe, middle pipe, inner pipe and nozzle body which is casted by vacuum pressure. The characteristics are: the hole of blowing oxygen is Laval hole, the ratio of exit and throat area is between 1.148¡«1.919, dip angle ¦Á of blowing oxygen hole between 80¡«260, and the amount of the hole between 2¡«20. Through contrast test, density and hardness of end surface of the Vacuum Pressure Casting lance nozzle is significantly increase compared with conventional casting nozzle, and density is improved because porosity, shrinkage cavity and shrinkage phenomenon is eliminated; the hardness is higher at an average of about 40 ~ 45HBS. Physical function of end surface, namely material density is increased, thermal and Electrical Conductivity is enhanced, mechanical function, namely tensile strength and hardness is strengthened. Because of improved density, the cooling and heat-resisting ability is strengthened correspondingly; and anti-impact and anti-corrosion capability is improved due to strengthened tensile strength and hardness. The stability of throat size of the vacuum Pressure Casting lance nozzle is improved, which maintains the stability of oxygen jet, makes the smelting more smoothly, and extends service life markedly.