Objective. Many studies indicate a link between vegetarianism and mental health, but the relationship remains uncertain. The aim of the present study is to examine the cross-sectional association between anxio-depressive symptomatology, happiness, and vegetarianism in a French sample while controlling for relevant confounders. Design. Self-reported questionnaire data were obtained from a large cross-sectional sample.Participants and setting. 9993 participants aged 18-99, 70.8% females participated in an online survey. Results. A logistic regression analysis was performed to estimate the Odds Ratio (OR) and 95% Confidence Interval (95% CI) of anxiety, depression, happiness, and self-reported health to predict vegetarian diet, controlling for age, gender, BMI, educational level, monthly income, and city size. Vegetarians did not present an increased risk of anxiety or depression. However, they reported lower happiness than did non-vegetarians, and exhibited better self-reported health than did omnivores. Conclusion. Vegetarian diet was not found to be related to anxiety or depressive symptoms. However, vegetarians presented lower levels of happiness. This result may be interpreted as a consequence of the social status of vegetarianism in France.