Objective: No studies so far have shown the effect of fruit and vegetable intake on mental disorders in Mexican Americans, for whom mental illness is an important health issue. This study measured the association of fruit and vegetable intake with the symptoms of cognitive impairment, the indication of increased risk of dementia, anxiety, and depression in Mexican Americans. Method: Participants were drawn from the Cameron County Hispanic Cohort (N = 3,943), a randomly selected Mexican American cohort in Texas on the United States–Mexico border. Consumption of fruit and vegetables and symptoms of four mental disorders were assessed using reliable and validated instruments. Results: Among 2,702 participants (mean age = 50 years, 34% male) with available data, 213 had cognitive impairment, 61 had the indication of increased risk of dementia, 626 had depression, 196 had anxiety, and 787 (29.13%) had mental disorders (i.e., any symptoms of the above four disorders). Participants who met recommendations of 5 or more servings of fruits and vegetables per day were less likely to have anxiety (OR = 0.22, 95% CI [0.08, 0.65], cognitive impairment (OR = 0.16, 95% CI [0.05, 0.46]), and indication of increased risk of dementia (OR = 0.16, 95% CI [0.03, 0.86]) compared with those who did not meet recommendations, after adjusting for covariates. Every portion increment of total fruit and vegetable intake was significantly associated with the reduced odds of mental disorders by 11% and the odds of cognitive impairment by 32%, with the adjustment of other covariates. No significant associations were found between fruit and vegetable intake and depression. Conclusion: Fruit and vegetable intake was inversely associated with symptoms of cognitive impairment, the indication of increased risk of dementia, and anxiety in Mexican Americans. Improving consumption of fruit and vegetables may be a convenient target for mental disorder-symptoms prevention and control among Mexican Americans, independent of other factors.