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Objective To investigate the association between low levels of benzene exposure (average intensity<0.05 parts per million [ppm]) and risk of colorectal cancer (CRC) including its anatomical subsites.Material and Methods Among the 25,347 men in the NOPW cohort with offshore work history between 1965 and 1998, we prospectively identified 469 CRC cases 1999–2021 and compared them with 2031 non-cases drawn from the cohort in case-cohort analyses. Work histories were linked to job-exposure matrices for benzene and other occupational exposures. Weighted Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for overall CRC and anatomical subtypes (right- and left-sided colon cancer [RCC and LCC] and rectal), adjusted for age, body mass index, smoking, alcohol intake, red/processed meat intake, and physical activity.Results Risks of CRC increased with increasing benzene exposure. For all CRC, the HRs (95% CI) for the most exposed [quartile 4] vs the unexposed were 1.32 (0.96 to 1.81, [0.177–0.879 ppm-years]; p-trend=0.085) for cumulative, 1.52 (1.11 to 2.07, [17–34 years]; p-trend=0.032) for the duration, and 1.56 (1.15 to 2.12, [0.015–0.046 ppm]; p-trend=0.005) for average intensity of benzene exposure. For right-sided colon cancer, the association was most evident for exposure duration (HR=2.25, 1.33 to 3.80, quartile 4 [17–34 years] vs. unexposed; p-trend=0.007). Sensitivity analyses showed consistent associations.Conclusion Our results suggest that risks of CRC, and particularly RCC, increased with increasing duration of rollover shift work and benzene exposure in male offshore workers.