The main goal of this study was to investigate the effect of exposure time and smoking habit on arsenic levels in biological samples of workers occupationally exposed to metals in comparison with non-occupational residents in Turkey. Blood, urine and hair samples were collected from 95 metal workers at Ankara Occupational Diseases Hospital, Turkey. Similarly, 94 hair samples were taken from controls. Arsenic levels in biological samples were measured using Graphite Furnace Atomic Absorption Spectrometry (GFAAS) equipped with Zeeman background correction and Hydride Generation Atomic Absorption Spectrometry (HGAAS). In metal workers; mean hair-arsenic levels of the smokers group (2.05 +/- 1.97 mg As/kg) was found to be significantly higher than the mean of the hair-arsenic levels of non-smokers group 1.80 +/- 1.79 mg As/kg (p<0.05). Mean hair-arsenic levels of exposure time group (4-10 years) was found (2.34 +/- 2.21 mg As/kg) to be significantly higher than the arithmetic mean of exposure time group (1-3 years) (1.39 +/- 1.25 mg As/kg, p<0.01). As for the control group, mean of hair-arsenic levels in the smokers group (0.133 +/- 0.012 mg As/kg) was found to be significantly higher than the mean of the hair-arsenic levels of non-smokers group (0.101 +/- 0.006 mg As/kg, p<0.05). In addition, mean hair arsenic level in metal workers (1.81 +/- 1.79 mg As/kg) was found significantly higher than mean hair arsenic level in control group (0.115 +/- 0.006 mg As/kg, p=0.00). Smoking increased the hair arsenic levels significantly both in metal workers and controls. The hair arsenic levels significantly enhanced with ascending exposure time. In addition, metal workers had significantly higher hair arsenic levels than controls. However, there was no significant effect detected in terms of urine and blood arsenic levels.