Taking design practice as an example, this paper aims to explore landscape design strategies and specific methods of non-drug therapy rehabilitation for mental illness patients, a vulnerable group. The purpose of the design is to help patients with mental illness have the ability to work and live, and return to the family and society, and enhance the harmony and happiness of patients' family and society. First, careful follow-up record and data deduction research method are used for special groups to obtain the potential needs of psychiatric patients who are extremely difficult to communicate and exchange. Second, through a psychiatric rehabilitation nursing knowledge and design of interdisciplinary research perspective, behavior needs are converted to design strategy, and simulation scenario type rehabilitation community innovation idea is put forward. Learning knowledge and skills under the guidance of a therapist is a preparation for returning to society by borrowing role-playing techniques from the game. Based on the behavioral needs, this paper proposes a situational simulation community method model, transplants landscape design methods into the treatment of mental illness, strengthens the role of rehabilitation landscape in curing mental illness, expands the field of vision beyond aesthetics and ecology of landscape design, and enriches the connotation of design science.