Abstract: Objective To analyze the association between the low level occupational and environmental exposures to benzene and concentrations of trans, trans-muconic acid (t, t-MA) and s-phenilmercapturic acid (S-PMA) in urine collected from exposed individuals.Methods Persons who worked with a shoe-lasting machine and were continuously exposed to glue in shoe factories in Guangzhou City were selected as occupational exposure group, and those who lived in newly decorated houses for more than six months were defined as environmental exposure group.Contents of t,t-MA and S-PMA in urine were detected by ultra-performance liquid chromatography tandem mass spectrometry.Airborne benzene was detected by gas chromatography method.Results The concentrations of airborne benzene were (0.16±0.06) mg/m3 (x±s) in occupational exposure group and 0.01（0.02）mg/m3 (M［ITQ］) in environmental exposure group.The concentrations of t,t-MA and S-PMA were (42.7±39.2) μg/g Cr and (0.28±0.19) μg/g Cr in occupational exposure group and 20.5 (16.2) and 0.03（0.04）μg/g Cr in environmental exposure group, respectively.Mann-Whitney U-test revealed that the concentrations of airborne benzene and t,t-MA, S-PMA were all higher in occupational exposure group than those in environmental exposure group (P<0.01 for all). Moreover, t,t-MA and S-PMA in urine were correlated with airborne benzene when the airborne benzene concentration was 0.16 mg/m3 (r=0.499,0.715).Conclusion t,t-M and S-PMA could be taken as biomarkers to apply in monitoring low level occupational and environmental exposures to benzene.