In a cryogenic infrared optical system, the temperature of processing and assembly of optics and its supporting structure is difference from the actual working environment. According to the requirements of cryogenic infrared optical system for optical machine structure design, a flexible supporting structure for cryogenic optical lens is designed and fabricated in this paper. The supporting structure of the optical lens is circumferentially equipped with a group of flexible and cantilevered supporting feet, which provide radial support for the optics. The waveform washer is used to provide axial support for the optics in the axial direction. Both schemes are important to avoid lens surface type not meeting indicator requirements due to temperature difference, physical property differences and changes in materials. The experimental result shows that the lens supporting structure has good imaging effect in the low temperature condition of 133 K.