Aims: This study was designed to evaluate the validity of urinary 1-hydroxypyrene as a biomarker in carcinogenic PAHs (cPAHs) exposed Iranian carbon anode plant workers. Materials and Methods: The study population consisted of 42 workers working in a carbon anode plant and control group consisted of 43 office workers. Personal air sampling was performed to assess workers atmospheric exposure to carcinogenic PAHs . Urine samples were collected for analysis of urinary 1-hydroxypyrene using high performance liquid chromatography (HPLC). Statistical analysis was performed with SPSS version 16 software. Results: The mean concentration of occupational exposure to cPAHs in the exposed group was 11.42±7.56 ΅g/m 3 . Mean level of urinary 1-hydroxypyrene in the exposed and control groups were 6.32±4.9 and 0.54±.48 ΅mole/mole creatinine, respectively . Urinary level of 1-hydroxypyrene in the exposed group was significantly higher than the control group (P<0.001). A strong and significant correlation between total cPAHs exposure and urinary 1-hydroxypyrene (r=0.79, P<0.001) was found . Conclusion: The results confirm urinary 1-hydroxypyrene level as a good biomarker in cPAHs exposed workers. In addition, considering the level of urinary 1-hydroxypyrene, it can be concluded that studied carbon anode plant workers are exposed to substantial risk of cancer and other genotoxic effects which are the result of cPAHs exposure.