Bacteria are not only cause the harmful disease to mammal, but most bacteria provide significant benefits to human by stimulating the immune system. Seed of Prunus persica (L.) Batsch has been known with a beneficial biological function, blood circulation activator and blood stasis breaker. The change of bacterial cell growth by the seed extract of Prunus persica (L.) Batsch was measured using colony forming unit method. Streptococcus epidermidis was tested as a beneficial skin commensal bacterium and S. aureus was tested as a skin pathogenic bacterium. The growth of S. epidermidis was enhanced by 57% while the growth of S. aureus was inhibited by 40% in a co-culture condition. This result suggested that the seed extract of Prunus persica (L.) Batsch had a skin prebiotic activity. The complex phytochemicals in an extract would be the significant key to change the bacterial growth in a strain specific way and the active chemicals will be identified in a further experiment. The discovered of additional benefit of seed extract of Prunus persica (L.) Batsch would provide opportunity to develop a new biological skin care product.