Abstract: In order to explore the substance basis of scalding tobacco, broad-targeted metabolomics was employed to analyze the variation in the metabolic components of scalding tobacco and evaluate the chemical components involved in browning-related pathways and tobacco leaf quality. The results revealed that a total of 2184 metabolites were identified in the scalding tobacco, with 211 showing differential abundance of which 148 showed up-regulation and 63 showed down-regulation. Among these differentially expressed metabolites, several alkaloids were significantly elevated in the scalding tobacco. KEGG enrichment analysis demonstrated that scalding tobacco affected various metabolic pathways, including ABC transporters, biotin metabolism, diterpenoid biosynthesis, galactose metabolism et al.. Browning of tobacco leaves resulted in a decrease in the levels of small molecule sugars such as sucrose, maltotriose, maltose, and trehalose, while the cellulose degradation product D-cellobiose exhibited a significant increase in scald tobacco. Moreover, the quinone component 2,3-dihydro-1,4-naphthoquinone was found to be significantly higher in scalding tobacco compared to orange tobacco, and it exhibited inhibitory effects on polyphenol components such as kaempferol and usnic acid. These results provide a biochemical basis for analyzing the causes of tobacco browning.