Abstract: 【Objective】 To investigate the effects of light on tomato fruit ripening through integrated transcriptome andmetabolome analysis, which could provide reference for exploring the molecular mechanisms underlying light-regulated tomato fruit development and efficient cultivation of tomato. 【Method】Using Lycopersicon esculentum cv. Ailsa Craig fruits as experimental materials, fruits at 29 d post-anthesis were either wrapped in black bags（ dark treatment group） or exposed to normal light（ control group）. Tomato fruit quality parameters of the 2 groups were measured. Transcriptome libraries of tomato fruits under different treatments were constructed by transcriptome sequencing（ RNA-Seq）, and diffe-rentially expressed genes（ DEGs） were screened. GO function annotation and KEGG signaling pathway enrichment analysis were performed on DEGs. Metabolites in tomato fruits were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry（ UHPLC-QTOF-MS） and their metabolomics were analyzed. Principal com-ponent analysis（PCA） was used to assess changes in metabolites and corresponding changes in gene expression of enzyme activity associated with fruit ripening. Real-time fluorescence quantitative PCR was used to verify the reliability of RNA-Seq data. 【Result】 Compared to the control group, carotenoid, lycopene and lutein contents of tomato fruits were extremely significantly reduced in the dark treatment group（P＜0.01, the same below）. Activities of sucrose phosphate synthase（SPS）, acid invertase（AI） and neutral invertase（NI） decreased significantly, while sucrose synthase（SS） activity extremely significantly increased in the dark treatment group. The numbers of up-regulated and down-regulated DEGs of tomato fruits in the dark treatment group and control group were 5833 and 5312 respectively. The response path-way of fruit to shading was similar. A total of 30 GO functional entries were identified by GO functional annotation; the KEGG signaling pathway enrichment results showed that the dark treatment group affected the metabolic pathway of pho-tosynthesis and secondary metabolite biosynthesis. The first principal component（PC1） of positive and negative ion modes explained 75.11% and 77.82% of the data variation, and PC1 mainly reflected the differences of organic acids and phenols（ core metabolic changes in the dark treatment group） between the groups. Signaling pathways related to photo-synthesis, hormone signal transduction, starch and sucrose metabolism were enriched the most obviously. Compared with the light group, 7 key genes related to tomato plant hormone biosynthesis pathway were screened in the dark treatment group, and the expression of squalene/octahydrolycopene synthase gene（PSY） was up-regulated and the expression of flavin-containing amine oxidorereductase gene（PDS） was down-regulated in the dark treatment group. The relative expression of genes under real-time fluorescence quantitative PCR was consistent with that of RNA-Seq. 【Conclusion】 Shading can inhibit the expression of genes related to photosynthesis, reduce light energy capture and carbon assimilation, and lead to chlorophyll accumulation and glucose metabolism imbalance in tomato fruits. In the dark treatment group, expression of key gene of carotenoid biosynthesis PDS in inhibited, resulting in the decrease of lycopene content and ulti-mately affecting the tomato fruit coloring.