The mature leaves of the salt treatment group with 1.0% NaCl solution and the control group with well water were selected for transcriptome and metabolome analysis to analyze the changes in the transcriptome and secondary metabolite levels of Bambusa distegia in the two studied material. The results showed that compared with the control group, a total of 487 expressed genes were detected with variation in the treatment group, including 257 up-regulated genes and 230 down-regulated genes. GO functional analysis of DEGs showed that DNA damage and methyltransferase complexes occurred in the leaves of Bambusa distegia under salt stress. The KEGG enrichment analysis of DEGs revealed that more enriched metabolic pathways related to carbohydrate and amino acid metabolism were found in Bambusa distegia, with the largest number of enriched secondary metabolite biosynthetic pathways. With salt treatment, a total of 225 differential secondary metabolites were identified, with 77 up-regulated and 148 down-regulated. Among them, one significantly differential secondary metabolite was up-regulated(log2(FC)≥1), which was trigonelline, and 20 were down-regulated(log2(FC)≤–1) and were mainly phenolic acids and flavonoids. Under prolonged salt stress, methylation complex regulation in the expressed genes of Bambusa distegia might stabilize gene expression, but salt stress still caused DNA damages in Bambusa distegia. By improving the primary metabolic capacity and reducing the downstream phenylpropanoid biosynthesis pathway, the contents of osmotic pressure regulating substances such as soluble sugar, soluble protein, and trigonelline in Bambusa distegia increased, maintaining osmotic pressure and ensuring physiological activity under salt stress.