The invention provides an insulation protective system for mechanical arms with cameras. The mechanical arms are mechanical arms of a hot-line robot. The cameras are externally sleeved with insulating sheaths, and each insulating sheath comprises a left side sheath body and a right side sheath body. The dimensions of the left side sheath bodies and the right side sheath bodies are slightly larger than those of the corresponding cameras, and the left side sheath bodies and the right side sheath bodies wrap the left half sides and the right half sides of the corresponding cameras separately. The cameras are exposed out. The left side sheath bodies and the right side sheath bodies are provided with buckles matched with each other. Camera signal line via holes are formed in the rear sides of the left side sheath bodies and the rear sides of the right side sheath bodies. Camera signal lines are wrapped with insulated hoses. Shoulder joints, big arms and small arms of the mechanical arms are all wrapped with buckle-type insulating sheaths made of silicone rubber materials . Wrist joints are externally sleeved with extensible corrugated insulation sleeves. By means of the insulation protective system, the effect that the cameras cannot be affected by a high-voltage electric field in the process of moving along with the mechanical arms is guaranteed, and therefore safety performance of the robot during hot-line work can be ensured, and the hot-line work efficiency and the automation level are improved.