There is a strong correlation between diet and mental health, and malnutrition can contribute to the development of various psycho-neurological diseases. Fatty acid profile plays an important role in the treatment of psycho-neurological diseases; therefore, the aim of the current study was to evaluate fatty acid profile in the diet of patients in three Latvian psycho-neurological hospitals. Latvian psycho-neurological hospitals submitted a detailed one-week menu. The information in the menus was processed using the Fineli program. Each menu identified the composition of fatty acids. The average fat concentration in different hospital menus ranged from 74.8 g to 96.1 g per day, where the concentration of saturated fatty acids ranged from 37.5 g to 47.7 g per day and the unsaturated fat concentration ranged from 35.9 g to 47 g per day. The n-3 PUFA content was consistent with the recommendations of a healthy individual, but it did not meet the needs of patients in a psycho-neurological hospital. The total eicosapentaenoic acid and docosahexaenoic acid concentration in the hospital menus ranged from 0.03 to 0.13 g, which was significantly lower than recommended, whereas LA and ALA concentration in hospital menus is close to optimal. The trans-fatty acids concentration in hospital menus did not exceed 2.5 g per day, with the exception of one day in hospital No. 2. The impact of diet on the treatment of psycho-neurological diseases in Latvian psycho-neurological hospitals has not been sufficiently assessed.