Schizophrenia ( SCZ ) is a severe mental disorder characterized by complex pathological mechanisms and high treatment resistance; it currently ranks among the diseases with the heaviest socioeconomic burden worldwide. Current antipsychotic medications are limited by factors such as insufficient response rates, limited cognitive improvement, and significant metabolic side effects. The ketogenic diet (KD), a metabolic intervention strategy characterized by high fat, low carbohydrate, and moderate protein intake. Although current clinical trials of KD for SCZ have small sample sizes, emerging data suggest that KD can effectively alleviate psychiatric symptoms,cognitive dysfunction, and abnormal metabolic parameters in some patients through multiple pathways, including modulating cerebral energy metabolism, reducing oxidative stress, and balancing neurotransmitter systems, showing significant clinical translational value. This article systematically reviews the research progress of the KD as an adjunctive treatment for SCZ, discussing mechanisms of action, preclinical evidence, clinical exploration, current challenges, and future research directions.