Abstract:Carotenoids and anthocyanins are antioxidant metabolites,which play an important role in the resistance of plants to photooxidative stress and contribute to the color of leaves,flowers,and fruits at the same time. The rich color metabolites of fruits are beneficial to human health. This article summarizes the effects of light signals on the biosynthetic metabolic pathways of plant carotenoids and anthocyanins,focusing on the regulatory mechanisms of important transcription factors involved in the light signal pathways of genes for synthesizing carotenoid and anthocyanin,and clarifies a significant role for light signals and photoreceptors in mediating the regulation of carotenoids and anthocyanins biosynthesis. Using sweet orange (Citrus sinensis) as an example,the light response elements of carotenoid and anthocyanin biosynthetic genes were analyzed. The major transcription factors including HY5(elongated hypocotyl 5),BBXs(BBOX containing proteins),COP1(constitutively photomorphogenic 1),PIFs(phytochromeinteracting factors),and HY5BBXs complexes,HY5PIFs complexes,HY5PIFsBBXs complexes,HY5COP1BBXs complexes that participate in these pathways are summarized. It provides an insight into the regulatory mechanism underlying of HY5,BBXs,COP1,PIFsmediated carotenoids and anthocyanins accumulation. Understanding the crucial role of the transcription regulation of carotenoid and anthocyanin mediated by light may help us to explore effective pathways and target genes for improving fruit quality and increasing the accumulation of carotenoid and anthocyanin via genetic engineering and environmental treatments.