Abstract: ObjectiveTo investigate the current status of Bacillus proteus infection among diarrheal patients in Maanshan city, Anhui province, provide the reference to establish the active surveillance system of food-borne diseases. MethodsThe stool samples of outpatients suffering from diarrhea were collected. By enrichment, isolation and culture, pure culture and biochemical, serological and limulus tests, the bacillus proteus detected were identified. Endotoxin and drug resistance tests were conducted for some strains. ResultsA total of 200 strains of pathogens were identified from 460 stool samples of diarrheal patients, in which bacillus proteus amounted to 131 strains (28.48%), including 115 strains of proteus mirabilis (25.00%) and 16 of proteus vulgaris (3.48%). Bacillus proteus accounted for 65.50% of all identified pathogens, ranking at the first place. Male and female patients accounted for 32.02% and 25.00%, respectively, which had no statistical significant difference, and the difference on infection rates among age groups had no statistical significance too. Among 80 strains of bacillus proteus to which endotoxin test was conducted, 64 strains were endotoxin positive (80.00%). ConclusionBacillus proteus might be the main pathogen that caused food poisoning and diarrhea in Maanshan city, to which attention shall be paid.