Abstract: As an important discipline for the construction of human settlements, landscape architecture provides important support for establishing a public security system for urban and rural spaces and promoting the health of residents. This research starts with unified development of landscape architecture and public health, and explores the supporting content and system of landscape architecture in promoting public health. It is of great significance for the development of the discipline. First, it analyzes the major public health crisis and the new situation of health risks at the present stage, and clarifies the significance of landscape architecture as the green infrastructure being capable of providing qualified public health services. Second, it explores three impact mechanisms, i.e., space & policies, factors & behaviors, landscape & emotion, of landscape architecture in promoting public health. It further discusses three major responses, i.e., supply, prevention and adjustment, of landscape architecture in actively responding to urban public health and coping with the urban public health crisis. Finally, it puts forward suggestions in three dimensions for supporting public health with landscape architecture: enriching disciplinary theory, improving green space supply, and innovating technological means. It is hoped to provide professional support for building a healthy and livable environment.