In recent years, the mortise-and-tenon scaffold system has gradually gained widespread recognition as a new type of scaffold system, owing to its advantages of ease of construction, safety, and efficiency. It has been applied in several practical engineering projects, bringing significant economic benefits and demonstrating broad development prospects. However, the current mortise-and-tenon scaffold still relies on traditional systems such as the coupler-type diagonal bracing. Therefore, this paper designs a new type of mortise-and-tenon diagonal bracing joint to fill the gap in the design of mortise-and-tenon scaffolding, further improving its structural system.