In order to study the effect of carbon resources on the operational performance of denitrifying sulfide removal process, the removal efficiency of sulfide, nitrate and organic carbon was investigated in UASB reactor, using sodium acetate and phenol as the carbon resources respectively. Meanwhile batch cultivation experiment was applied to study the degradation and conversion of carbon, nitrate and sulfide. The results showed that the removal efficiency of NO₃^--N, S^2-and Ac^--C would reach 93%, 90% and 99% under a 2.5-10 h HRT, respectively, using sodium acetate as carbon source. Under such condition the accumulation rate of elemental sulfur remained stable at about 41%. For a comparison, the removal efficiency of NO₃^--N, S^2- and C₆H₅O^--C was 67%, 85% and 50% respectively using phenol as carbon resource (10 h HRT), however the sulfide was converted to sulfate completely and no elemental sulfur accumulated. The results of batch cultivation experiment showed that the oxidation rates of S^2-, acetates and S⁰ displayed in such order: q_S^2- > q_Acetate > q_S⁰ when the sodium acetate was used as carbon resource; however, the oxidation rates of S^2-, phenol and S⁰ using the phenol as carbon resource distributed in the trend of q_S^2- > q_S⁰ > q_Phenol.