The application of nursing is a guarantee of quality healthcare processes; however its use in the care of people with mental illness is very limited. Objective: To improve the quality of the care for people with mental illness through the application of theoretical knowledge and the development of skills gained from the implementation of nursing process in a home care program of a third level mental health Institution in the Colombian Southwest. Method: descriptive transversal research; 38 people diagnosed with schizophrenia participated. The evaluation according to the functional patterns of health by Marjory Gordon was used, from the period of January to June 2010. Results: 4 altered patterns maintained above 20% were identified: activity and exercise, metabolic nutrition, relation and cognitive sensory roles. The intervention of nursing was oriented from promotional and preventive approaches with specific care according to requirements of the patient. Discussion: It is required to encourage the application of nursing process in the population of people with mental illness to ensure a whole and quality care, which seeks to involve the family as a dinamic element of recovery process of the subject involved.