OBJECTIVE Existing information regarding the impact of physical activity after a cancer diagnosis on all-cause mortality is limited. We examined the association between different types of physical activity (domestic, walking, sports) and mortality in 293 participants (65.5% women) with a cancer registration prior to the baseline assessment. METHODS Participants were drawn from the Scottish Health Surveys (1995, 1998, 2003) that were linked to a national database of cancer registrations and deaths. The main outcome was all-cause mortality during a mean follow-up period of 5.9 +/- 3.2 years. Cox proportional hazards models were used to estimate the risk of all-cause mortality by levels of physical activity. RESULTS There were 78 deaths during follow-up. The lowest risks for all-cause mortality were seen in sports activity groups [multivariable-adjusted hazard ratio (HR) for any compared with groups of no sports: 0.47, 95% CI 0.23-0.96, p = 0.039] although light and moderate activity such as domestic activity (HR = 1.04, 0.60-1.80) and regular walking (HR = 0.95, 0.57-1.56) did not confer protection. CONCLUSION Participation in an average of more than three sessions of vigorous exercise per week for at least 20 min/session was associated with the lowest risks of all-cause mortality following a cancer diagnosis. Vigorous physical activity could therefore be a more important determinant of survival than duration or total volume of exercise in cancer survivors.