The infection of the orbita and ocular tissues can result in severe local and systemic complications. We aimed to determine the predisposing factors for preseptal and orbital cellulitis, the clinical and routine laboratory differences between orbital and preseptal cellulitis, and the change in the spectrum of the pathogens and the antibiotics used in the last 10 years. One hundred thirty-nine patients, hospitalized in Hacettepe University Faculty of Medicine Children's Hospital between 1 January 1990 and 31 December 2003 with diagnosis ofperiorbital or orbital cellulitis, were reviewed retrospectively. Ten of the patients (7%) had orbital and 129 (93%) had preseptal cellulitis. The male/female ratio was 1.7:1. The average age (mean+/-standard deviation) was 5.7+/-4 years. The seasonal distribution was most marked in spring and fall periods. When compared with preseptal cellulitis, the mean blood cell count, erythrocyte sedimentation rate and C-reactive protein levels were significantly higher in patients with orbital cellulitis. Staphylococcus aureus was isolated in 13 (41.9% of total microbiologically confirmed cases), coagulase-negative staphylococcus in 8 (25.8%), and H. influenza type b in 2 patients (6%). Thirty out of 77 clinical sample cultures (39%) were positive. In clinical studies, etiological agents of orbital and preseptal cellulitis could be identified in only 20-30% of cases, so in clinical practice treatment is usually empiric. We observed that sulbactam-ampicillin was a safe and effective choice of treatment in orbital and preseptal cellulitis in our cases.