Chitosan and its derivatives, which are known to possess multiple functional properties, have attracted considerable interest due to their biological activities and potential applications in the pharmaceutical, food, agricultural and environmental industries. Many researchers have focused on chitosan as a potential source of bioactive material in the past few decades. This study focuses on the antibacterial and antitoxin activity of chitosan against S. aureus and it's enterotoxin type C. Chitosan inhibit growth of S. aureus which inoculated at 10⁵ in yoghurt at 5^th day in all trails at different concentrations (conc.) (0.5, 1 and 2%). Enterotoxin type C inhibited at 10^th day at 0.5% conc. in yoghurt. While, at 1% and 2% conc. of chitosan complete inhibition of toxin occurred at 6^th day. Positive control trial, the toxin still detected until the end of the experiment. Chitosan haven't flavor, but have 55% of consumers were strongly agree to addition of  0.5% chitosan, 40% of consumers to 1% chitosan and 20% for 2% chitosan. The conc. of chitosan at 1and 2% have the same antibacterial and antitoxin effect, so this study advised to use chitosan at 1% conc. to reduce the public health hazards of S. aureus and it's enterotoxin.