Flexibility and light weight are beneficial to reduce load, reduce volume, and integrate device, and is the development trend of space science and technology. However, most spacecraft photoelectronic devices are rigid devices now, because the space environment consists of multiparticle radiations and thermal cycling, with higher requirements for flexible photoelectronic materials and devices. The main technical bottlenecks include: the fabrication of flexible photoelectronic materials and devices, the synthesis of space-durable packaging materials, and the integration of flexible optoelectronic devices and packaging materials. In view of these problems, this paper studies the synthesis of bulk-phase modified transparent and yellow polyimides with space durability, the fabrication of transparent flexible electrode based on bulk-phase modified polyimide film and one-dimensional silver nanowires, the integration of the bulk-phase modified transparent polyimide and thin-film triple-junction GaAs solar cell, and the mechanism of space radiations on the above flexible photoelectric materials and devices. The material synthesis, device fabrication, and mechanism analysis of this study focus on the scientific problems of space-durable flexible lightweight photoelectronic materials and devices, which benefits the development of flexible and lightweight space science and technology.