Metabolomics analysis based on UPLC-MS/MS was used to investigate the influence of rain shelter (RS) conditions on metabolites of sweet cherry leaves. It was found that there were 134 differential metabolites. These differential metabolites were enriched in 40 metabolic pathways. Studies on the biosynthetic pathways and regulatory mechanisms of metabolites in sweet cherry leaves showed that low-light and drought stresses in RS plants were related to the amino acid biosynthesis metabolic pathway and that of flavone and flavonol biosynthesis. Sweet cherry trees exhibited improved tolerance to drought stress by regulating the increase in the content of metabolites, such as proline in the amino acid metabolic pathway and the content of flavonoids in the phenylpropane metabolic pathway. To cope with low-light stress, sweet cherry leaves can increase their photosynthetic efficiency by regulating the flavonol content in the flavone and flavonol biosynthetic pathway under the catalysis of a series of enzymes.