The invention discloses a system for visually detecting the surface flaws of the small-diameter reflective spheres in batches. The system comprises a control system, a bottom plate, an alcohol tank fixedly installed on the bottom plate, and a sphere feeding unit, a sphere automatic classifying unit, a light source and visual driving unit which are controlled by the control system. A sphere lifting unit and a sphere transmission unit which are electrically connected with the control system are fixedly installed in the alcohol tank, the sphere feeding unit is communicated with the sphere lifting unit, and a detection block is arranged in the alcohol tank; a light source and visual shooting unit is suitable for moving the small spheres on the sphere lifting unit to the detection block for surface unfolding shooting and transmitting the shot pictures to the control system for analysis, meanwhile the detected small spheres are moved to the sphere transmission unit, and the output end of the sphere transmission unit is communicated with a sphere automatic classification unit. The system has the advantages of safety, reliability, continuous detection, high detection rate, high precision and the like, the cost is saved, and the system has broad markets and urgent demands in bearing sphere production enterprises.