Histone modification is an important mechanism of epigenetic regulation. New histone modifications play key roles in the regulation of gene expression and in the development and progression of various diseases. In addition to histone modifications, epigenetic regulation includes classic pathways such as DNA methylation, chromatin remodeling complexes and non‑coding RNAs, which interact with each other and jointly shape the occurrence and development of gastric cancer (GC). The present study systematically elaborated on the role of histone modification in GC and introduced several main types of histone modification, including acetylation, methylation, citrullination, ubiquitination and lactylation, focusing on histone lactylation modification and exploring its biochemical basis, interaction with other modifications and functions such as metabolic reprogramming, cell proliferation, migration and immune escape, covering non‑tumor and other cancer fields. On this basis, the specific application of histone modification (acetylation, methylation and other modifications) in GC is further explained and the effects of histone lactylation on metabolic reprogramming, proliferation, migration and immune escape of GC are analyzed in detail. Finally, the clinical significance of histone lactylation modifications in the diagnosis and prognosis of GC, biomarkers, therapeutic targets and drug resistance mechanisms provides a reference for an in‑depth understanding of the role of histone modifications, especially lactylation modifications, in the development of GC and clinical transformation applications.