<![CDATA[This research is motivated by the strong role of television as the main promotional medium, as well as the vital function of the tagline and brand ambassador in shaping positive consumer perceptions, especially among the Millennial Generation who are the primary target market for the Collagena milk product. This quantitative survey-based study aims to analyze (1) the partial effect of the Tagline (X₁), (2) the partial effect of Brand Ambassador Song Hye Kyo (X₂),and (3) the simultaneous effect of both variables on the Brand Image (Y) of Collagena milk among millennials in Jl. SD Inpres RT 008/RW 006, Pulo Gebang Sub-district, Cakung District, East Jakarta. The research employs the Stimulus-Organism-Response (S-O-R) Theory framework, where the promotional variables act as stimuli processed by consumers. The study sample consisted of 110 Millennial respondents selected through a purposive sampling technique. Data were collected using questionnaires, literature review, and documentation. Data analysis was performed using validity tests, reliability tests, classical assumption tests, and multiple linear regression analysis. The results indicate that both the tagline and brand ambassador, partially and simultaneously, have a significant influence on Brand Image. The Brand Ambassador proved to be the most dominant variable (β = 0,649) The Coefficient of Determination R² value of 0.889 suggests that 88.9% of the variation in Brand Image is explained by these two independent variables. The study concludes that the appropriate marketing communication strategy employed by Collagena effectively creates a very positive perception and strong brand image among millennials. Keywords : Tagline, Brand Ambassador, Brand Image, Song Hye Kyo, Abstrak Penelitian ini dilatarbelakangi oleh kuatnya peran media televisi sebagai sarana promosi utama, serta fungsi vital tagline dan brand ambassador dalam membentuk persepsi positif konsumen, khususnya di kalangan Generasi Milenial yang merupakan target pasar utama produk susu Collagena. Penelitian kuantitatif berbasis survei ini bertujuan menganalisis (1) pengaruh tagline (X₁), (2) pengaruh brand ambassador Song Hye Kyo (X₂) secara parsial, dan (3) pengaruh kedua variabel secara simultan terhadap citra brand (Y) susu Collagena pada generasi milenial di Jalan SD Inpres RT 008/RW 006, Kelurahan Pulo Gebang, Kecamatan Cakung, Jakarta Timur. Penelitian ini menggunakan kerangka Teori Stimulus-Organism-Response (S-O-R), di mana variabel promosi bertindak sebagai stimulus yang diolah konsumen. Sampel penelitian berjumlah 110 responden yang dipilih melalui teknik purposive sampling, dengan data dikumpulkan melalui kuesioner, studi pustaka, dan dokumentasi. Analisis dat dilakukan dengan uji validitas, uji reliabilitas, uji asumsi klasik dan uji regresi linier berganda. Hasil penelitian menunjukkan bahwa tagline dan brand ambassador secara parsial maupun simultan berpengaruh signifikan terhadap citra brand. Brand ambassador terbukti menjadi variabel yang paling dominan (β = 0,649). Nilai Koefisien Determinasi R² sebesar 0,889 mengindikasikan bahwa 88,9% variasi citra brand dijelaskan oleh kedua variabel tersebut. Kesimpulannya, strategi komunikasi pemasaran Collagena yang tepat mampu membentuk persepsi dan citra brand yang sangat positif di kalangan milenial. Kata Kunci : Tagline, Brand Ambassador, Citra Brand, Song Hye Kyo]]>
