To assess the prognostic factors of recurrence after endoscopic sinus surgery for maxillary chronic rhinosinusitis without nasal polyps.Prospective.Tertiary referral center.A total of 411 patients were operated on for maxillary chronic rhinosinusitis without nasal polyps (307 rhinogenic rhinosinusitis, 74 odontogenic rhinosinusitis, and 30 oroantral fistula cases) in a single institution between 2002 and 2007. Ten parameters were analyzed to study their relationship with recurrence: etiology of rhinosinusitis, partial resection of middle turbinate, smoking history, allergy, asthma, gastroesophageal reflux, preoperative endoscopic score, CT stage, maxillary sinus mucosa score, and bleeding score. Preoperative characteristics and recurrence rates were compared with the analysis of variance test. Failure was analyzed as a time-dependent variable by the Kaplan-Meier method. Variables identified on univariate analysis were entered into a multivariate Cox proportional hazards model.Recurrent rhinosinusitis developed in 28 (6.8%) cases. In the univariate analysis, preoperative endoscopic score, CT stage, and bleeding score were associated with recidivism. However, the multivariate analysis suggested that only bleeding is an independent predictive factor of recurrence (P = 0.034, 95% confidence interval for odds ratio 0.92-7.21).Intraoperative bleeding may be a risk factor for failure in endoscopic surgery of maxillary rhinosinusitis, but there is substantial uncertainty and future research is needed.