Abstract: A method for determination of titanium content in ferrosilicon nitride by diantipyrylmethane（DAPM） spectrophotometry was investigated.Some condition experiments were done,which includes decomposition of samples,smoking of sulfuric acid,coloring,interference and eliminating method,and the optimal conditions were obtained.The sample was fused and decomposed with 3 g sodium hydroxide in an iron crucible at 650 ℃.The sintered mass was dissolved with 50 mL hot water,and then the solution was acidified with 10 mL hydrochloric acid and 5 mL hydrofluoric acid. The silicon and residual hydrofluoric acid in the solution was removed by total 7 mL sulfuric acid for two times of smoking.The Fe （Ⅲ） ion was reduced by ascorbic acid to eliminate the interference of iron in the solution.After the reaction with diantipyrylmethane in 2 mol/L hydrochloric acid medium at room temperature,the solution was measured at absorption wavelength of 390 nm by photometer.A detection limit of 0.02% for this method was also obtained by experiments.At last,this method was applied to the determination of some ferrosilicon nitride standard samples,good accuracy and precision were evidenced with 0.05%~2.00% of titanium content.