Background: Few researchers have investigated the incidence of and risk factors for hospital-acquired pneumonia (HAP) among inpatients with mental disorders in a general hospital.Methods: This study included patients with mental disorders hospitalized in a large mental health center (situated in a general hospital) between January 1, 2017 and July 31, 2021 (excluding January 1, 2020 to May 31, 2020). Risk factors for HAP were identified by logistic regression analysis after propensity score matching (PSM, 1:4) for gender, age, duration of observation and hospital ward.