Abstract: A differential pulse cathodic stripping voltammetric method for determination of Sudan Ⅰin food was proposed.In a base solution of B-R buffer of pH 5,the adsorptive voltammetric behavior of Sudan I at the glassy carbon electrode was studied under the conditions of accumulation at the potential of -0.47 V (vs.Ag/AgCl) for 180 s with scanning rate of 50 mV·s-1,and a sensitive reduction peak was observed at -0.43 V (vs.Ag/AgCl).Linear relationship between values of peak current and concentration of Sudan I was kept in the range of 1.2×10-7-8.1×10-5mol·L-1.Detection limit (3S/N) found for the method was 4.0×10-8mol·L-1.The method was applied to the analysis of pepper powder,giving value of average recovery 99.3%.