Abstract: Pulse amperometry with separation by ion exchange chromatography was applied to the determination of hydrogen sulfide (H2S) in mainstream of cigarette smoke. H2S in mainstream of cigarette smoke was trapped in a mixture containing solutions of 100 mmol·L-1 NaOH-400 mmol·L-1 sodium acetate-0.5% ethylene diamine-20 mmol·L-1 ascorbic acid. IonPac AS7 anion exchange column was used as separation column and a mixture containing solutions of 100 mmol·L-1 NaOH-400 mmol·L-1 sodium acetate-0.5% ethylene diamine were used as eluant in the elution. In the pulse amperometric detection, silver electrode was used as working electrode, pH/Ag/AgCl electrode was used as composite reference electrode. Linear relationship between values of peak area and mass concentration of S2- was obtained in the range of 0.1-5.0 mg·L-1, with detection limit of 1.52 μg·L-1. Test for recovery was made by addition of the standard of S2- to sample of mainstream of cigarette smoke as the matrix, values of recovery obtained were in the range of 92.4%-96.4% with RSD′s (n=6) in the range of 2.0%-3.3%.