Tujuan dari penelitian ini adalah untuk meneliti bagaimana pengaruh dari kelima faktor yang meliputi Trustworthiness, Expertise, Attractiveness, Similarity, dan Attitude Toward the Influencer terhadap Attitude Toward Advertisement sebagai mediasi yang kemudian mempengaruhi faktor Purchase Intention pada produk somethinc di media sosial TikTok. Pengujian model penelitian ini yang dimodifikasi dari penelitian terdahulu dilakukan secara kuantitatif dengan data survei. Responden dipilih melalui purposive sampling, dan kuesioner disebarkan secara online. Dari responden yang memenuhi syarat, sebanyak 200 sampel dianalisis dengan menggunakan Partial Least Squares Structural Equation Modeling (PLS-SEM). Hasil penelitian menunjukkan bahwa kelima variabel indepeden yaitu, Trustworthiness, Expertise, Attractiveness, Similarity, dan Attitude Toward the Influencer memiliki pengaruh yang signifikan dan positif terhadap Attitude Toward Advertisement. Selain itu, Attitude Toward Advertisement dapat memediasi secara signifikan dan positif pengaruh dari kelima variabel independen tersebut terhadap Purchase Intention. Serta, Attitude Toward Advertisement memiliki pengaruh yang positif dan signifikan terhadap Purchase Intention. Implikasi manajerial dari penelitian ini dapat dipergunakan sebagai pertimbangan pengembangan produk berdasarkan variabel-variabel yang sudah diteliti oleh penelitian ini. / This study aims to examine how the influence the five factors that include Trustworthiness, Expertise, Attractiveness, Similarity, And Attitude Toward the Influencer to Attitude Toward Advertisement as mediation which then influences factors Purchase Intention on Somethinc products in TikTok social media. Testing of this research model, which was modified from previous research, was carried out quantitatively with survey data. Respondents were selected through purposive sampling, and questionnaires distributed online. Of the respondents who met the requirements, 200 samples were analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM). The research results show that five independent variables are, Trustworthiness, Expertise, Attractiveness, Similarity, And Attitude Toward the Influencer has a significant and positive influence on Attitude Toward Advertisement. In addition, Attitude Toward Advertisement can mediate significantly and positively the influence of the five independent variables on Purchase Intention. As well as, Attitude Toward Advertisement has a significant and positive influence on Purchase Intention. The managerial implications of this research can be used as a consideration for product development based on the variables that have been examined by this research.