Abstract: Objective To analyze the prevalence and pathogen of acute meningitis and encephalitis in Guigang city,Guangxi Zhuang Autonomous Region.Methods A surveillance network for detection of acute meningitis and encephalitis cases was set up in Guigang,which covered all the population in Guigang and 12 hospitals at county level and above.Suspicious cases were selected and evaluated according to disease screening criteria.All cases met the diagnostic criteria received a questionnaire survey and their blood and cerebrospinal fluid(CSF)samples were collected.Bacteriological culture and detections of 10 common viral IgM with PCR and enzyme-linked immunosorbent assay(ELISA)were conducted for the samples.Data were input and analyzed by using Epi Info 2002.Results During the surveillance period from May 2007 to April 2008,a total of 883 cases met the diagnostic criteria with 41 cases of death.The bacteriological pathogens of the cases included Streptococcus pneumoniae(Sp.),Neisseria meningitides(Nm),haemophilus influenza B(Hib),and Streptococcus suis.The enteroviruses,mumps virus and Japanese encephalitis(JE)viruses were the main pathogens of viral encephalitis.The incidence rate of bacteriological and virus encephalitis for the city were 0.92/100 000 and 6.42/100 000,respectively.Most of the cases occurred in summer and autumn and were under 10 years old.Conclusion The main cause of acute encephalitis and meningitis in Guigang city was viral infections.The incidence of bacterial encephalitis and meningitis is at a low level.