BACKGROUND The great majority of mental disorders begin during adolescence or early adulthood, although they are often detected and treated later in life. To compare mental health status of college students and their non-college-attending peers whether working, attending a secondary school, or non-college-attending peers who are neither employed nor students or trainees (NENST) will allow to focus on high risk group. METHODS Data were drawn from a large cross-sectional survey conducted by phone in 2005 in four French regions in a randomly selected sample of 22,138 adults. Analyses were restricted to the college-age subsample, defined as those aged 18 to 24 (n = 2424). Sociodemographic, educational, and occupational status were determined. In addition, respondents were administered standardized instruments to assess mental health and well-being (CIDI-SF, SF-36, Sheehan Disability Scale, CAGE), mastery, social support, and isolation. The four occupational groups were compared. All analyses were stratified by gender. RESULTS Mental health disorders were more prevalent among the NENST group, with significant differences among men for anxiety disorders including phobias, post-traumatic stress disorder (PTSD) and panic disorder, impairing at least one role in their daily life. This was also true among women except for panic disorder. The NENST group also reported the lowest level of mastery and social support for both genders and the highest level of social isolation for women only. After adjustment, occupational status remained an independent correlate of PTSD (OR = 2.92 95 % CI = 1.4-6.1), agoraphobia (OR = 1.86 95 % CI 1.07-3.22) and alcohol dependence (OR = 2.1 95 % CI = 1.03-4.16). CONCLUSIONS Compared with their peers at work or in education/training, the prevalence of certain common mental health disorders was higher among college-aged individuals in the NENST group. Efforts should be made to help young adults in the transition between school or academic contexts and joining the workforce. It is also important to help youths with psychiatric disorders find an occupational activity and provide them information, care, support and counseling, particularly in times of economic hardship. Schools and universities may be adequate institutional settings to set health promotion programs in mental health and well-being.