The invention relates to a control loop of safe and nondestructive testing of a strength conveyor belt. Due to the facts that capacity value of the strength conveyor belt is increased and the strength conveyor belt is scratched and aging and other facts, the malfunctions that a steel wire rope core cracks and is rusted, a connector extends long and the like are caused, once the malfunctions occur, a major safety accident can be caused, production is stopped, losses of transport materials, damage of devices and huge economical losses and casualties can be caused, and safety production is seriously influenced. The control loop of the safe and nondestructive testing of the strength conveyor belt comprises an infrared emitter set, a switching circuit, a photovoltaic conversion circuit, an acquisition circuit and a controller, wherein the infrared emitter set, the switching circuit, the photovoltaic conversion circuit, the acquisition circuit and the controller are all connected with a power source, the controller is connected with an alarm circuit, and the controller is connected with an upper computer through an RS485 communication interface. The control loop of the safe and nondestructive testing of the strength conveyor belt is high in accuracy, safe, reliable, convenient to install and use, and capable of carrying out detection in an on-line and real-time mode and avoiding occurrence of major safety accidents, reduces the losses of the transport materials and the economical losses, and improves production efficiency.