This paper aims to assess impact of influencers on the online purchasing behavior of Generation Z in the cosmetics industry in Vietnam. The research model uses six characteristics of influencers as independent variables. Cronbach Alpha test, and linear regression analysis were applied and used to identify and evaluate factors affecting the online purchasing behavior of Generation Z in the cosmetics industry in Vietnam. Data were collected from 300 Gen Z customers from three regions (North, Central, South) in Vietnam. Microsoft Forms were the tool used to collect data. The results show that influencers have significant impacts on intention to purchase comestics online of Gen Z customer in Vietnam, all six characteristics of influences have significantly postive relationship with intention to purchase comestic products online. Among all characteristics of influencers, expertise is the most significant determinants of online cosmestic purchase intention, and familiarity between influencers and customers has the second highest impact on online comestics purchase intention.