Objective To understand the baseline of spices (Chinese prickly ash, pepper, star anise) and to provide the basis for quality and safety inspection of spices. Methods 106 batches of spices were freshly picked from different origins and then dried naturally. They were preprocessed into two groups:grinded and ungrinded group, which were determined by titration and ion chromatography respectively.SPSS 20.0 software was used for statistical analysis to evaluate the baseline of sulfur dioxide. Statistical differences were analyzed between grinded and ungrinded group and between titration and ion chromatography methods. Results The mean baseline of sulfur dioxide in 106 batches of Chinese prickly ash, pepper and star anise were 0.141,0.079,0.202 g/kg, the content range in 0.03-0.30,0.01-0.16 and 0.04-0.41 g/kg. The confidence intervals under the 95% confidence probability were 0.131-0.152,0.073-0.085 and 0.189-0.215 g/kg. There were no statistical differences between the two determination result of grinded and ungrinded group(t=0.768,P>0.05). There were no statistical differences between the two detection method of titration and ion chromatography either(t=0.692,P>0.05). Conclusion The three kinds of spices all have the baseline of sulfur dioxide. The maximums of confidence intervals under 95% probability were used as the baseline of sulfur dioxide content of the three spices.