Digital technology and social media are gradually changing the traditional methods of marketing as the spread of social media has further changed buying and selling techniques. People are affected by what they see on social media platforms and from this comes a new marketing method that is applied by many businesses and has become a worldwide phenomenon, and that is marketing using influencer marketing. Many businesses entering the Vietnamese market choose to invest in influencer marketing who post their reviews and opinions about a product or service that is well received by consumers.

The research is about the influencer characteristics affecting the purchase intention of the followers, in which, attitude is the intermediate variable based the Ohanian model 1990 by using a quantitative research method. To test the framework hypothesis, the formal quantitative study was based on a survey sample of 212 consumers. The research results of the thesis show that the online shopping intention of consumers is affected by trustworthiness, attractiveness, and attitude, in which the value of attractiveness and attitude is the highest. In contrast, expertise has no relationship with purchase intention.

Through the research, it is concluded that influencers' characteristics play a large role in the purchase intention of consumers regarding online purchases. The research results confirm that the factors mentioned above play an important role in attracting attention and influencing the change of mind of customers about online purchases. With these contributions, marketers can make the best and most profitable decisions when deciding to collaborate with social media influencers.

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