Anecdotal evidence has suggested that constructed wetlands can reduce malodor in liquid livestock wastes. This study quantified the concentrations of two malodorous compounds (dimethyl disulfide and p-cresol) and evaluated odor intensity and offensiveness of liquid swine manure treated in constructed subsurface-flow wetlands. Correlations between concentrations of the aforementioned compounds and odor intensity and offensiveness levels were also examined. Four wetlands planted with wetland grasses and four unplanted wetlands were loaded with liquid swine waste from a campus grower-finisher facility. Dimethyl disulfide (DMDS) and p-cresol concentrations in the liquid swine waste were quantified using gas chromatography. A human sensory panel rated odor intensity and offensiveness levels (IL) of wetland effluent using the cloth swatch technique. Wetland effluent was significantly lower (p<0.05) in DMDS and p-cresol concentrations than raw manure. Furthermore, IL ratings were significantly lower (p<0.05) for wetland effluent than untreated manure. Spearman’s rank-order correlation coefficient was used to test correlations between average IL ratings and DMDS and p-cresol concentrations. Spearman coefficients, R, were 0.752 and 0.699 between average IL ratings and DMDS and p-cresol concentrations, respectively (p<0.05). The associations between average IL ratings and the malodorous compound concentrations were not higher because of the discrepancy between concentrations of pure compounds and the complex odor characteristics of the compound mixture in liquid swine manure.