In view of the current situation that ground-based telescopes in the field of deep space detection have difficulty in directly ranging of the object, research on efficient ranging using the sun as an external radiation source was carried out. The idea of using the sun as an external radiation source for the direct ranging of deep-space object was firstly proposed. The ranging scheme based on the intensity fluctuation of the sunlight between the direct wave and the reflected wave by the object was established. Next, the feasibility and engineering difficulties of this scheme were also simulated and analyzed. Finally, the simulated solar radiation source was successfully used to achieve object ranging in the laboratory environment. The demonstration and implementation of this scheme is expected to provide high precision ranging capability for existing optical survey telescopes, and provide a new idea for establishing an efficient deep space detection system.