Abstract:China characterized by extensive saline-alkali and arid land, along with low utilization rate of marginal lands. As an important tuberous root crop, sweetpotato plays a significant role in ensuring national food security. Therefore, identifying important stress-resistance genes in sweetpotato and developing new resilient varieties can effectively utilize these saline-alkali, arid, and marginal lands, thereby significantly enhancing the utilization efficiency of land resources. GAPCp1, a glyceraldehyde-3-phosphate dehydrogenase located in plastid, plays a crucial role in plant growth, development, and energy metabolism. In this study, using the sweetpotato variety Lizixiang (LZX) as the material, we successfully cloned the open reading frame (ORF) sequence of IbGAPCp1. Subcellular localization studies showed that the protein encoded by IbGAPCp1 is localized in chloroplasts. Quantitative real-time PCR analysis showed that IbGAPCp1 is expressed in all tested tissues of sweetpotato, with the highest transcription level in leaf tissues. The expression of IbGAPCp1 gene increased gradually with the development of sweetpotato tuberous root and reaching its peak at 105 days. In order to further explore the regulatory mechanism of IbGAPCp1 gene, we cloned a 1940 bp sequence of the IbGAPCp1 gene promoter, designated as Pro-IbGAPCp1. The prediction of cis-acting elements showed that Pro-IbGAPCp1 contains several elements related to photoresponse, hormone response and meristem expression. Under drought and salt stress treatments, IbGAPCp1 gene exhibited a trend of first increasing and then decreasing, indicating that this gene responds to drought and salt stress. Additionally, 35 upstream regulators interacting with the promoter region of IbGAPCp1 were screened by yeast one-hybrid technique, including ethylene-insensitive protein 2, sucrose synthase 2 and MYB44. These factors are involved in plant growth and development, secondary metabolism, energy production, and various stress responses, such as drought, salt and low temperatures. This study provides a theoretical basis for further study on the function and mechanism of IbGAPCp1 in response to abiotic stress in sweetpotato.