Abstract: Oral malodor, a common oral symptom, is primarily caused by the metabolic activities of oral microorganisms. The characteristic odors mainly originate from volatile sulfur compounds produced and released by oral bacteria (such as Fusobacterium nucleatum and Porphyromonas gingivalis) through specific enzymatic systems that break down sulfur-containing amino acids in saliva, gingival crevicular fluid, and food debris. Research indicates that various factors, including periodontitis, fungal infections, smoking, and obesity, can worsen oral malodor by altering the oral microenvironment. For prevention and treatment, novel interventions such as plant extracts, antimicrobial peptides, and probiotics demonstrate superior microbiological safety compared to traditional antimicrobial drugs. These approaches specifically inhibit pathogenic bacteria, disrupt biofilm structures, and regulate oral microbial balance. This review summarizes relevant research advances to provide new theoretical foundations and practical directions for the precise prevention and treatment of oral malodor.