Abstract: Monodisperse SiO₂ microspheres with particle size in the range of 208—368 nm were prepared by the Stöber method and used to construct structural color films via fast lifting method. The as-prepared structural color films were then embedded in polydimethylsiloxane (PDMS), on which polydopamine (PDA)-doped PDMS (PDMS-PDA) was coated to obtain stretchable color-changing PDMS/SiO₂/PDMS-PDA photonic elastomer films. Both the structural color films and photonic elastomer films were explored with techniques including scanning electron microscope, nanoscale laser particle size analyzer, spectrophotometer, fiber optic spectrometer, tensile testing machine and digital camera to elucidate the microstructure and optical properties of the former and the strain response and mechanical properties of the latter. Results show that the structural color films belong to amorphous photonic crystals consisting of long-range disordered and short-range ordered arrangements of SiO₂ microspheres, and their structural colors are angle-independent under diffuse light. But interestingly, the structural colors are angle-dependent under sunlight due to the surface of SiO₂ microspheres arranged flatly. As for the photonic crystal elastomer films surface-coated with a black PDMS-PDA layer, the saturation of the structural color of the films during stretching is greatly improved. When the tensile strain reaches 20%, the films start to show apparently structural color, which undergo a continuous blue-shift with increasing strain, and the color returns to the initial state when the strain is restored. Moreover, the film has good mechanical properties with an elongation at the break of 140%, and can be applied to the field of visualized flexible sensing, smart wearable devices and other fields.