This paper described the use of caring theory on a case involving a patient suffering from major depressive disorder with psychosis. Through holistic nursing assessment, we discovered that the patient and family members lacked stress coping skills, the patient's perception was disorganized, and compliancy to medication was poor. We assisted the patient and caregiver to: realize that negative thinking could affect their emotions; understand psychotic symptoms; learn symptom management skills; join therapeutic group to strengthen insight, all in order to enhance his will in continuing treatment by application of Watson caring theory. During hospitalization, the patient's depressed mood improved gradually, his psychotic symptoms including auditory hallucination decreased, his drug compliance and coping skill improved, and his interaction and communication with his family also became more effective. Base on the post discharge follow-up program, we realized he had good drug compliance and regular outpatient clinic visits. These implied that we could focus on the connection between mood status and psychotic symptoms during clinical nursing care to prevent relapse.