A modified method is descnlxd for the use of 0.5M sulfuric acid-0.5M tartaric acid as a supporting electrolyte in the polarographic determination of titanium. The interferences due to iron (Ⅲ) and copper are rcduced with iron powder. In comparing with Graham's method, the amount of tartaric acid reduces to half, and the removal of interferences by iron powder proves more simple and effective than Graham's and Zan'ko's methods. The method is applied to copper, lead, zinc and titaniferous iron ores with satisfactory results.