OBJECTIVE To investigate the spectrum of organisms causing purulent endophthalmitis and to identify the variance of bacterial spectra and their sensitivities to commonly used antibiotics.METHODS The medical records of patients with purulent endophthalmitis receiving pathogen examination in Zhongshan Ophthalmic Center from Jan 2000 to Dec 2006 were analyzed retrospectively.RESULTS Of the 416 cases,82.0% purulent endophthalmistis were caused by ocular trauma and the organisms were isolated in 181(43.5%)of them.Among the pathogens isolated,14.9%,47.5%,9.9% and 27.6% were fungi,Gram-positive cocci,Gram-positive bacilli and Gram-negative bacilli,respectively.The fungal endophthalmistis was sporadic per annum.The most common bacterial pathogen was staphylococcus epidermidis(33.1%) which increased year by year.The most common Gram-negative bacterium was Escherichia coli(10.5%).Among the common pathogens,the Gram-positive cocci were sensitive to fluoroquinolones and cefoperazone,and the Gram-positive bacilli were sensitive to aminoglycosides and cefoperazone while the Gram-negative bacilli were resistant to various kinds of antibiotics in different degree.CONCLUSIONS The purulent endophthalmistis should be monitored in patients with open ocular injury.Fluoroquinolones with cefoperazone to treat the ocular inflammation are a preferred therapeutic regimen for patients with bacterial endophthalmitis with unknown etiopathogenesis.