Abstract : Meningitis is a serious deadly disease with high mortality if not rapidly treated. The typical clinical features of fever, neck stiffness and headache had poor diagnostic sensitivity. The need of rapid early detectection methods are needed to rescue patients. Few studies are conducted in Egypt for early detection of acute meningitis. The aim of this study is to determine the clinical charateristics and causative agents of acute meningitis among hospitalized febrile patients. A prospective cross sectional observational study. The study included 350 cases admitted with suspected meningitis. Lumbar puncture: for collection of cerebrospinal fluid (CSF) samples. CSF analysis, microbiological examination of CSF, and blood culture and antibiotic sensitivity test were done. Brain magnetic resonant imaging (MRI) was performed before lumbar puncture in some patients. Detailed analysis of epidemiologic characteristics, clinical data and laboratory findings, the causative organisms, prognosis of all the patients with acute bacterial meningitis (ABM) were studied. Meningitis occurred at all age groups. A significant proportion of meningitis patients (60%) reported a positive history of antibiotic intake in the few days (3-5) before admission to the hospital. 79.1% of ABM patients had a CSF leukocyte count in the range of > 100 up to 1,000 cell/mm3 and 80% had CSF neutrophil percentage > 50%. The pathogens were detected by direct Gram-stained smear in 86.4% of patients. Gram +ve bacteria was detected in 55/110 (50%) of cases. Gram -ve bacteria detected in 40/110 (36.4%) of cases. ABM carried a high mortality rate (22.7%). ABM had 22.7% mortality rate. Meningitis is endemic in Egypt with a significant mortality rate. Strept. pneumonia was the most common offending organism. Clinicians should be aware of the dynamic changes of acute meningitis for rapid diagnosis and earky administration of suitable therapy.