The sharp rise in the incidence rate of colorectal cancer (CRC) in Korea over the past decades may be partlyattributed to increase in alcohol consumption. An ecological study was conducted in Korea to determine theassociation between alcohol consumption and the risk of colorectal cancer. We obtained the CRC incidence ratesfor the years 1999−2007 from the Korean Central Cancer Registry and the data on national alcohol consumptionfor the years 1998, 2001, 2005, and 2007 from the reports of the Korea National Health and Nutrition ExaminationSurvey. Pearson’s correlation coefficients were determined using data for alcohol intake and CRC incidencerate. People who consumed more than 45 g alcohol/day were defined as heavy drinkers. A significant correlationbetween alcohol consumption and the CRC incidence rate was observed in men; Pearson’s correlation coefficientswere statistically significant for men (r = 0.99; P = 0.001), but not for women (r = 0.82; P = 0.180). In the <50-yearage group, the age-specific incidence rate for men was comparable to that for women, but in the ≥50-year agegroup, it increased rapidly in men. The increase in alcohol consumption appears to be attributable to increasein the number of heavy drinkers among men aged 25−59 years, particularly among men aged 45−49 years. Ourfindings may aid in predicting future CRC incidence in Korea.