Background - Major behavioural risk factors are known to adversely affect health outcomes and be strongly associated with mental illness. However, little is known about the association of these risk factors with mental well-being in the general population. We sought to examine behavioural correlates of high and low mental well-being in the Health Survey for England. Methods - Participants were 13 983 adults, aged 16 years and older (56% females), with valid responses for the combined 2010 and 2011 surveys. Mental well-being was assessed using the Warwick-Edinburgh Mental Well-being Scale (WEMWBS). ORs of low and high mental well-being, compared to the middle-range category, were estimated for body mass index (BMI), smoking, drinking habits, and fruit and vegetable intake. Results - ORs for low mental well-being were increased in obese individuals (up to 1.72, 95% CI 1.26 to 2.36 in BMI 40+ kg/m2). They increased in a linear fashion with increasing smoking (up to 1.98, 95% CI 1.55 to 2.53, >20 cigarettes/day) and with decreasing fruit and vegetable intake (up to 1.53, 95% CI 1.24 to 1.90, <1 portion/day); whereas ORs were reduced for sensible alcohol intake (0.78, 95% CI 0.66 to 0.91, ≤4 units/day in men, ≤3 units/day in women). ORs for high mental well-being were not correlated with categories of BMI or alcohol intake. ORs were reduced among ex-smokers (0.81, 95% CI 0.71 to 0.92), as well as with lower fruit and vegetable intake (up to 0.79, 95% CI 0.68 to 0.92, 1 to <3 portions/day). Conclusions - Along with smoking, fruit and vegetable consumption was the health-related behaviour most consistently associated with mental well-being in both sexes. Alcohol intake and obesity were associated with low, but not high mental well-being.