The image transmission beam is a flexible passive image transmission device. Its structure is to integrate many optical fiber monofilaments of a certain length into a bundle. The monofilaments at both ends are closely arranged in a one-to-one correspondence. After curing and grinding, they become the image transmission beam. The optical fiber image transmission bundle can transmit images in a soft and curved state, realizing image transmission in dangerous and environments where human eyes cannot directly observe. It can be used in strong magnetic field, electric field, high and low temperature, high humidity and vibration environment.