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The aim of this study was to investigate the prevalence, molecular characteristics and antimicrobial susceptibility of S. aureus in raw eggs during production and sales in Yangling, Shaanxi Province, China, and assess whether enterotoxin-A-carrying strains could grow and produce enterotoxin A (SEA) in egg contents at 3 different temperatures (10, 25, and 37 °C) and culture times (1, 3, 5, and 7 days). A total of 102 isolates of 627 fresh eggs were identified, including 100 (15.9%) isolates from eggshells and 2 (0.3%) isolates from egg contents. All isolates harbored at least one virulence gene, hemolysin genes and novel enterotoxin genes were commonly detected. 95.1% of isolates were multi-drug resistant, with most commonly resistant to penicillin, trimethoprim, erythromycin, ciprofloxacin, and tetracycline. CC5-ST5-t002 (78.4%) was the most predominant clone. PFGE analysis found that isolates between the eggshell and egg contents of the same egg had the same dendrogram. In the test for artificial contamination of egg contents with S. aureus , three isolates could grow and produce SEA. This study indicates eggshells are often contaminated with high levels of S. aureus , and the discovery of S. aureus in egg contents implies the risk of entering the food chain. • The eggshell is often contaminated with high levels of S. aureus during production and sale. • Most S. aureus isolates harbored at least one virulence gene and exhibited multi-drug resistance. • CC5-ST5-t002 S. aureus was the dominant type among 102 S. aureus isolates. • Close genetic relatedness of S. aureus from eggshell and egg liquid was found based on PFGE analysis. • S. aureus could grow and product SEA at 10 °C, 25 °C and 37 °C in egg contents. [ABSTRACT FROM AUTHOR]