Background: Polycyclic aromatic hydrocarbons (PAHs) are among the most carcinogenic, mutagenic and toxic contaminates. Their exposure and metabolism to DNA-reactive metabolites in the body are considered to contribute to the etiology of many types of the human cancers. Objectives: To find out if exposure to polycyclic aromatic hydrocarbons is a risk factor for development of hepatocellular carcinoma (HCC) among the exposed cases, to detect if the smoking is an augmented factor for development of hepatocellular carcinoma among exposed cases, and to find the effect of socio-demographic characteristics of cases of hepatocellular carcinoma exposed to hydrocarbons. Subjects and Methods: A case control study was conducted between the period from the first of March 2015 to end of August 2017. The study was conducted in the outpatient clinic of the Department of Hepatology and Gastro-entrology at Theodor Bilharz Research Institute (TBRI). The minimum sample size required for the present study was calculated using Epi info program, considering following data: Two sided confidence level = 95%, power of test = 80%, ratio of control: cases = 1:1, percent of control exposed = 21%, percent of cases exposed = 42 %, and odds ratio = 2.8. Kelsey estimated number of cases = 77 and number of control = 77 subjects. All subjects of both groups were interviewed. Every patient was subjected to the selected interview sheet and biological monitoring of urinary 1-hydroxy pyrene as a biomarker for PAHs exposure. Results: 73% of cases of HCC had increased level of 1-hydroxy pyrene in urine with statistical significance difference when compared to controls. There was a significant positive association between exposure to PAHs and development of HCC among case group (OR = 4.9). There was a significant association between smoking and abnormal high level of 1-hydroxy pyrene in urine (OR = 1.7) among the case group. There was a significant positive association between exposure to PAHs and development of HCC among males (OR = 1.6). There was neither statistical significance difference nor positive association between exposure to PAHs and development of HCC in urban areas (OR=0.8). There was a statistically significant positive association between exposure to PAHs and development of HCC among smoker (OR=1.7). There was neither statistical significance nor positive association between exposure to PAHs and development of HCC among patients with chronic active hepatitis C (OR=0.6). There was a highly positive correlation between 1-hydroxy pyrene and Alfa Feto Protein (AFP) among positive cases of 1-hydroxy pyrene in case group (OR=316.25). Conclusion: Exposure to PAHs is considered as a risk factor of HCC among cases of hepatitis B and C. HCC cases had increased level of 1-hydroxy pyrene in urine with statistical significance difference when compared to controls. A significant positive association between exposure to PAHs and development of HCC among males and smokers were also detected.