6 . 5 % Si high silicon steel was manufactured by using CVD method and the process was introduced, the influence of temperature on the siliconizing rate and quality reducing rate, diffusion time on silicon distribution were investigated.Results as follows: the siliconizing rate will increase quickly when the temperature is higher than 1050 ℃ ,but the siliconizing rate will become steadily as the temperature up to 1200 ℃ ; The quality reducing rate will increase with the elevating of temperature and the rate will become steadily when the temperature is higher than 1200 ℃ ; The silicon will be well-distributed as the diffusion time is very sufficient, but it will be the highest efficient time when the Δw_表-中/ b≤5 .