Abstract: As a kind of signal molecule, carbohydrate regulates crop growth and development and ecological adaptation under drought stress. To explore the molecular mechanisms of potato（Solanum tuberosum） tuber responding to drought stress, the potato ′Cooperation 88′ was used as the experimental material in this study. Transcriptome sequencing was performed on potato tuber samples under diffe-rent degrees of drought stress by Illumina Hiseq 2500 sequencing technology and the obtained differentially expressed genes were annotated. The enzyme genes related to starch and sucrose metabolic pathways were further screened, and five genes were randomly selected for real-time quantitative PCR gene expression verification. A total of 4 476 genes were up-regulated and 4 490 genes were down-regulated in potato tuber under different degrees of drought stress. A total of 164 differentially expressed genes were found under the three treatments. KEGG metabolic pathway annotation suggested the enrichment of differentially expressed genes was the largest in carbohydrate metabolism and amino acid metabolism. Five key enzyme genes（SS, TPS11, SPS2, BGLU12 and BACOVA＿02659） involved in the metabolic synthesis of starch and sucrose were screened out, and 5 genes including CATHB1, CKA2F, GRXS17, PABN1 and RFS2 were randomly selected for real-time quantitative PCR detection. Transcriptome sequencing results were consistent with the expression levels detected by real-time quantitative PCR, which proved the reliability of transcriptome data. Ten genes are involved in the regulation of starch and sucrose metabolic pathways in potato tubers under drought stress. The results can help to elucidate that molecular mechanisms of differentially expressed genes in starch and sucrose metabolism in potato, and explored the pathways of starch synthesis and decomposition, sucrose breakdown and glucose synthesis under different degrees of drought stress.