Abstract: OBJECTIVE To analysis the clinical status of hospital infection and research characteristics and drug resistance of pathogenic bacteria of Alzheimer’s patients, meanwhile to analyze the possible reasons for targeted prevention. METHODS The information of elderly alzheimer’s patients medical records was collected with the method of retrospective survey. The Alzheimer’s disease in elderly patients in neurology, elderly and cadre wards in the hospital diagnosed with in the above several psychiatric hospital from January 2008 to December 2008. Then the characteristics of the pathogen resistance and possible infection reason was analyzed. The bacteria identification and drug sensitive test was in strict accordance with the national clinical test procedures. We did the experiments with drug sensitive test using the K-B method and Methicillin-resistant staphylococcus aureus detection using cefoxitin paper method recommended by CLSI. RESULTS Among the survey of 2 826 cases of Alzheimer’s patients, the occurrence of nosocomial infection in 276 cases, 304 cases, infection rate was 9.77%, the cases of infection rate was 10.76%. The infection following respiratory tract was the most common, followed by the upper respiratory tract, and then followed by the digestive tract, urinary tract, skin and mucous membrane, blood and other parts, and furthermore the respiratory tract infection accounted for 60% of all hospital infection. The 384 strains pathogenic bacteria were isolated in 304 specimens. Of 48 specimens detected 2 or more bacterial species, 21 patients exist many site infection. 281 strains of gram-negative bacteria, accounted for 73.18% of the total bacteria, 74 strains of gram positive bacteria, accounted for 19.27%, fungi accounted for 7.55%. Staphylococcus aureus was mest common in gram-positive bacteria up to 34 strains, most accounted for 8.85% of all pathogenic bacteria, gram negative bacillus with Pseudomonas aeruginosa were 84 strains, accounting for 21.88% of all pathogenic bacteria. CONCLUSION There was a greater incidence of hospital infection and bacterial drug resistance at the same time Pseudomonas aeruginosa, Klebsiella pneumoniae and E. coli bacterium for elderly alzheimer’s disease are the main pathogenic bacteria in three hospitals in Zhejiang province.