Objective To provide reference basis for the prevention， control and disposal of similar events in the future， the suspected food and pathogenic factors of a foodborne disease outbreak involving several kindergartens were investigated and traced.Methods Pathogen was detected in 32 samples collected from three kindergartens by rapid detection techniques （real time fluorescence PCR and mass spectrometry） combined with traditional identification methods， such as isolation and culture， enzyme linked immunosorbent assay （ELISA）. Descriptive epidemiological investigation method and pulsed field gel electrophoresis （PFGE） were performed to analyze the molecular traceability of pathogenic factors.Results There were 568 children in the three kindergartens， and 62 （10.92%） cases were found. The clinical manifestations were vomiting， diarrhea and so on. Staphylococcus aureus was detected in 10 biological samples and 2 preserved shredded pork floss cakes distributed by the same catering company. The plate counts of S. aureus in this two cakes were 2.0×10⁷ CFU/g and 1.4×10⁷ CFU/g， respectively. Staphylococcus enterotoxin gene type A （sea） and enterotoxin type A （SEA） were detected simultaneously from 11 isolates of S. aureus strains in patients and suspicious food. PFGE fingerprint showed the same type， suggesting the case and food isolates were the same exposure source.Conclusion The outbreak in three kindergartens was caused by the shredded pork floss cake contaminated with Staphylococcus enterotoxin， which distributed by the same catering company. The supervision of school food materials should be further strengthened.