Objective To determine the risk factors contributing to the recurrence of chronic subdural hematoma(CSDH). Methods The clinical data of 115 CSDH patients who received burr-hole irrigation in our hospital were retrospectively analyzed. Univariatie and multivarite analyses were performed to describe the relationships between CSDH recurrence and possible risk factors, including age, sex, Glasgrow Coma Scale (GCS) score, hepertension, diabetes mellitus (DM), with or without post-operative drainage, and observations of hematoma douche fluid. Results Recurrence of hematoma was found in 11 patients (9.6%). Two variables were found to be independently associated with the recurrence of CSDH: diabetes mellitus and blood clot and floc in hematoma douche fluid (P<0.05). The other variables were not found to be significantly correlated with recurrence of CSDH. Conclusion Presence of blood clot and floc in hematoma douche fluid is a risk factor of CSDH recurrence, and history of DM is also closely related to post-operation CSDH recurrence.