Abstract: Metabolic reprogramming is one of the significant characteristics of malignant tumor development. It provides the tumor with sufficient energy and materials. During the process by which tumor cells acquire metabolic reprogramming, epigenetic changes play a crucial role. N6-methyladenosine (m6A) in mRNA is the most common post-transcriptional modification of mRNA. It regulates the transcription, maturation, translation, and degradation of mRNA. Studies have shown that m6A helps promote the metabolic reprogramming of tumor cells. However, the complete mechanism still requires further research. METTL3 is a key enzyme for m6A methylation that catalyzes m6A progression by forming complexes with other proteins, such as METTL14 and WTAP. Notably, the critical role of METTL3 in the metabolic transition of gastrointestinal tumors has not been given due attention. This article summarizes the specific pathways through which METTL3 affects the reprogramming of cellular glucose metabolism in gastrointestinal tumors. We aimed to clarify the importance of METTL3 in the energy reprogramming of gastrointestinal tumors.