The effect of argon flow intensity on mass loss rate in the carbothermic reduction of SiO2 to SiC was examined. The graphite and natural quartzite in a molar ratio of C/SiO2=3 were used. Samples were reduced for 6 hours at 1 500 °C. In the range of argon flow intensity from 0,1 to 3,4 dcm3/min, the high level of rate of mass loss of the sample and the 70 – 80 % of SiC formed in the residue of the sample were obtained