Abstract: In the consideration of problems in producing process, such as high oxidation of refining slag, the fluctuation of T.O content in molten steel and calcium yield rate, the inclusion control technology had been researched in the high quality tube steel. The refining slag and producing technology had been researched, the T.O content was reduced and stable. The calcium treatment technology had been confirmed based on the thermodynamic calculation and laboratory research. Industrial tests showed that T.O mass fraction was not more than 15×10-6, w（Cat）/w（Als）was not less than 0.07, w（Ca）/w（S）was not less than 1.9 when the research countermeasures were applied. The modification of inclusion was improved. Every type of inclusions was not more than 1.0 level and A+B+C+D was not more than 3.0 level. The inclusion control met the quality requirement of the steel.