In this study, the emission characteristics of landfill gas (LFG) were investigated with respect to reduced sulfur compounds (RSC) and elemental mercury. To describe their emission characteristics accurately, methane and dilution-to-threshold (D/T) ratio were also analyzed as reference. LFG samples were collected in three different pathways; (1) old landfill (LF), (2) new LF, and (3) composite from both LFs. Differences in RSC concentrations between two LFG samples were relatively insignificant in the case of H2S, CS2, and SO2. On the other hand, a significant reduction in CH3SH and DMS concentrations was observed from old landfill. The concentration data of Hg and methane showed a similar spatial trend between new and old LF, as seen from RSC. In general, a large quantity of trace gas pollutants came out from new rather than old LF. The correlation analysis indicated strong relationship between most sulfur compounds, while it is not for other components including Hg, CH4, and D/T ratio. It suggests that trace composition of LFG comply well with the maturity of landfill.