A small but consistent literature from the United States suggests increased risk for smoking among lesbians and men who have sex with men (MSM). Few studies have investigated smoking among MSM in other countries where different social norms and restrictions on smoking in public apply. We measured smoking behaviours in a convenience sample of urban-dwelling young Canadian MSM (median age 28 years). We compared the prevalence of smoking among MSM with that among other men in British Columbia (BC) using National Population Health Survey data to compute an age-adjusted standardized prevalence ratio (SPR). Independent predictors of smoking among MSM were identified using adjusted odds ratios (OR) with 95% confidence intervals (CI). Smoking during the previous year was reported by twice as many MSM (54.5% of 354) as other men in BC (25.9%) (SPR = 1.94, 95% CI 1.48-2.59), with largest differentials observed among men under 25 years of age. In multivariable analyses, smoking among MSM was significantly associated with younger age (OR 0.94, CI 0.88-1.00 per year), greater number of depressive symptoms (OR 1.12, CI 1.06-1.19 per symptom) and Canadian Aboriginal ethnicity (OR 2.64, CI 1.05-6.60). In summary, MSM in our study were twice as likely to smoke as other men in BC; the greatest differences were observed among the youngest men. The design of effective prevention and cessation programs for MSM will require identification of the age-dependent determinants of smoking initiation, persistence, and attempts to quit.