Abstract: In order to study the transmission of S. aureus in chicken houses to their ambient air， the air samples， including indoor， upwind (10， 50 m) and downwind air (10， 50， 100， 200， 400 m) of 4 chicken houses were collected using Andersen-6 stages sampler and RCS. The S. aureus concentration of every sampling site was calculated. Chicken feces samples were collected according to the standard method and S. aureus was isolated. S. aureus was used as an indicator in this study.The repetitive extragenic palindromic elements PCR (REP-PCR) method was applied to generate genomic amplification products of S. aureus isolated from the chicken feces and the air. By analyzing the different concentration and genetic similarity of S. aureus in every sampling site， the transmission of bioaerosol from chicken houses to their ambient can be identified. The results showed that the S. aureus indoor concentration in 4 chicken houses were higher than those of upwind and downwind sites(P＜0.05 or P＜0.01)， but there were no significantly differences of S. aureus concentration among every downwind site (P＞0.05). The fingerprints and the phylogenetic tree indicated that a part of the S. aureus (38.7%) isolated from indoor air had the same REPPCR fingerprints with those isolates isolated from feces， the most of S. aureus isolated (55.9%) from downwind 10， 50， 100， 200 even 400 m had the same REP-PCR fingerprints with those isolated from indoor air or feces too， which indicated that some isolates isolated from downwind air and indoor air originated from the chicken feces. However， those isolated from upwind air had the low similarity coefficients (60%-87%) with those isolated from indoor air or feces. It was concluded that the isolates isolated from upwind air didn′t come from the chicken feces or indoor air. In a word， the S. aureus in chicken feces can be aerosolized and transmitted into the indoor and outdoor air， especially the downwind air of the chicken houses with the air exchange. This study revealed the transmitting rule of airborne S. aureus bioaerosol to the ambience.