Objective: To explore the effects of establishing high dependency unit (HDU) on the prognosis, outcome, and expenditure of patients with severe community acquired pneumonia (SCAP).Method: Data pertaining to 108 SCAP patients were retrieved from the respiratory intensive care unit (RICU) of the Second Affiliated Hospital of Chongqing Medical University, Chongqing, China. Of these, 87 qualified the study-selection criteria and were divided into HDU group (treated in HDU after discharge from RICU prior to transfer to normal unit) (n=40) and normal group (not treated in the HDU) (n=47). General condition of patients, APACHE II and SOFA scores, duration of mechanical ventilation, hospital infection, intensive care unit syndrome, length of stay, and expenditure were compared between the two groups.Outcome: There was no significant between-group difference with respect to noninvasive ventilation time, oxygenation index, or APACHE II and SOFA scores at admission or discharge from RICU (P>0.05). Fourteen patients in the HDU group received invasive ventilation; the mean invasive ventilation time (176±160 h) was not significantly different from that in the normal group (206±179 h). The period of sequential noninvasive ventilation in the HDU group (135±82 h) was significantly shorter than that in the normal group (274±182 h, P<0.05). HDU group had shorter length of stay in hospital and RICU, and incurred lesser expenditure than patients in the normal group (P<0.05).Conclusion: Patients in HDU group had almost the same therapeutic effect with shorter length of stay in hospital and RICU, and lesser expenditure.