To explore the effect of infection on hyperglycemic hemichorea. The clinical data of 11 patients with hyperglycemic hemichorea admitted to the Affiliated People' s Hospital of Xinxiang Medical College and the Second People's Hospital of Xinxiang were retrospectively analyzed, including gender, age, clinical symptoms, imaging features, blood glucose, glycated hemoglobin, infection indicators, and treatment conditions. Eleven patients had acute or sub-acute onset, including 9 females and 2 males, with an average age of 74.55 years. Nine patients presented with unilateral limb involuntary movement and 2 patients presented with bilateral limb involuntary movement. Imaging findings of 9 patients showed abnormalities in the basal ganglia region. Random blood glucose levels were all elevated at admission, with an average blood glucose value of 26.20 mmol/l. Urine ketone bodies were positive in 2 patients, inflammatory indexes were elevated in 7 patients, symptoms of hypoglycemic treatment and anti-infection treatment in 10 patients disappeared, and symptoms of 1 patient disappeared after improved microcirculation treatment. The disease tends to occur in middle-aged and elderly women, and the blood glucose may fluctuate significantly during the onset. Infection may lead to the occurrence and development of the disease. Active control of blood sugar, inflammation and improvement of brain metabolism can effectively control symptoms and prevent recurrence.