Using Kjeldahl distiller pretreatment and electronic titrator titration to determine sulfur dioxide residue in samples, and analyze the content of sulphur dioxide in food.Methods According to the distillation and titration of sulfur dioxide residue from 1 125 samples of 29 kinds, detection limit, precision and standard recovery of this method were further studied and test data were analyzed. Results The detection limit of Kjeldahl distillation-electronic titration iodine titration method was 0.010 g/kg, with RSD of 2.4%-5.1% and standard recovery of 87.0%-99.6%. Among the total of 1 125 samples, 20.8% were detected with sulfur dioxide, and 19.1% were detected but did not exceed the limit of maximum residue.Conclusion Kjeldahl distillation-electronic titration iodine titration method is rapid, accurate, and suitable for sulphur dioxide detection in food. Among several samples such as candied fruit, biscuit, vermicelli and dried shrimp, the sulfur dioxide residues were exceptional and higher than the limit of maximum residue in China, which is a potential safety risk.