Metabolic memory (MM) is a major factor in the delayed wound healing observed in diabetic patients. While "Nocardia rubrum cell wall skeleton" (Nr-CWS) is utilized to enhance macrophage proliferation in immune diseases, its impact on MM wounds in diabetes is unclear. This study demonstrates that transient hyperglycemia leads to prolonged damage in vascular endothelial cells by decreasing METTL3 expression, leading to decreased RNA methylation and impaired cellular metabolism. Remarkably, Nr-CWS application increases METTL3 levels in these cells, facilitating the recovery of cell function. Further in vivo and in vitro analyses demonstrate that transient hyperglycemia-induced reduction in METTL3 hinders RNA methylation of the downstream gene Cds2, impacting mitochondrial function and energy metabolism and consequently reducing angiogenic capacity in endothelial cells. This impairment significantly influences diabetic wound healing. Our findings highlight the profound impact of transient hyperglycemia on wound healing, establishing METTL3 as a significant role in vascular complications of diabetes. This study not only elucidates the pathophysiological mechanisms behind MM in diabetic wounds but also suggests Nr-CWS as a potential therapeutic agent, offering a novel approach for treating diabetic wounds.