Lactate promotes the transition of wound macrophages to a reparative phenotype and accelerates wound healing in mice by activating PKM2. Eighteen mice were randomly divided into three intervention groups: the CTRL group (treated with vehicle, n = 6), the LA group (treated with 20 mM lactate, n = 6), and the LA+Pi group (treated with lactate + 1.2 µM PKM2 enzymatic inhibitor, n = 6). Immunofluorescence staining with iNOS + CD68 (A) or ARG1 + CD68 (B) was performed to analyze wound macrophages on Day 5 post-injury. Scale bar = 100 µm. n = 6. (C) The photographs of skin wounds and schematic diagram of comparison of wound area on Day 3 and Day 9. Scale bar = 5 mm. (D) Statistical results of relative wound area (fold of the wound on Day 3). # means the statistical difference between the LA and LA + Pi groups, * means the statistical difference between the LA and CTRL groups. (E) Relative wound areas on Day 9 (Fold of the wound on Day 3) were analyzed (n = 6). (F) Skin wound hematoxylin and eosin (HE) staining on Day 5. Scale bar = 400 µm. (G) Skin wound HE staining on Day 12. Data represents mean ± SEM, *p < 0.5, **p < 0.01, ##p < 0.01.