Abstract: Sulfur is an important quality and environmental indicator in vanadium-titanium magnetite ore, so the accurate measurement of sulfur is of great significance for subsequent process control and pollution evaluation. There are some problems such as integration delay and poor precision in low sulfur when measuring sulfur in vanadium-titanium magnetite ore with the high-frequency combustion infrared absorption method. To solve the problems, scanning electron microscope (SEM) and infrared absorption carbon-sulfur analyzer with programmed heating function were used, and the analysis conditions such as power, flux and addition sequence, and sample mass were optimized. The optimized experimental conditions were as follows: analysis power of 95%, iron particle flux of 0.30g, copper particle flux of 0.20g, and tungsten particle flux of 1.0g, sample mass of 0.30g. The order of addition is iron-copper-sample-tungsten. The optimized method was used to measure sulfur content, and the results of sulfur in the standard sample were within the allowable error, with satisfactory accuracy. The relative standard deviation (RSD) in samples was 0.40%−0.67%, with satisfactory precision. The range of the method was 0.0004%−1.52%, and the detection limit was 0.0004%.