Abstract: Based on properly designed chemical composition, the billet for pipe-making in a new austenite heatresistant steel SP2215 is successfully produced by means of the conventional manufacturing process for the billet for the heat-resistant, hi-pressure boiler steel pipe.Compared with the HR3C heat-resistant steel, the SP2215 steel shows such advantages as low alloy element content, relatively low production cost, the more excellent thermal plasticity and the better suitability for the 2-high rotary piercing process.Moreover the hi-temperature durance strength of the SP2215 steel under 650 ℃ and 700 ℃ is obviously better than the HR3C steel, while the resistance against hi-temperature steam oxidative corrosion and the weldabiity of the said two steels are equal to each other.Therefore it is regarded that the comprehensive performance of the SP2215 steel is obviously better than the HR3C steel, and worthy using as the heatresistant steel for the 620~650 ℃ ultra-supercritical power plant boiler.