Phuong Thy Nguyen

The growing dominance of social media as a marketing platform underscores the importance of understanding how influencer credibility affects consumer behavior. Social media influencers, through effective personal branding and content creation, form strong connections with their followers, significantly impacting their audience’s perceptions, attitudes, and purchasing decisions. This study explores the effects of social media influencers’ source credibility, comprising trustworthiness, expertise, and attractiveness, on consumers’ purchase intentions and behaviors regarding beauty products in Vietnam. A quantitative approach was utilized, with data collected from 269 Vietnamese consumers through a structured questionnaire and analyzed using partial least squares structural equation modeling. The results showed that all three components of source credibility, including trustworthiness, expertise, and attractiveness, significantly and positively influenced consumers’ purchase intentions for beauty products. Among these factors, expertise had the strongest effect on purchase intention (β = 0.289, p < 0.001), followed by trustworthiness (β = 0.216, p = 0.001), and attractiveness had the weakest influence on purchase intention (β = 0.195, p < 0.001). Moreover, purchase intention was found to have a significant positive impact on purchase behavior (β = 0.545, p = 0.004). These findings provide valuable insights for marketing managers and companies seeking to optimize their influencer partnerships by selecting influencers whose credibility aligns with their brand values and leveraging their expertise to build consumer trust, drive engagement, and influence purchase decisions.

Acknowledgement
The researchers express sincere gratitude to all the participants who participate in this research study.