Purpose: TikTok Shop was launched with the aim of helping small and medium businesses in Indonesia develop their business digitally. Since its launch, TikTok Shop has been committed to becoming a platform that can be used by local business owners, especially SMEs, to develop their businesses on digital platforms. TikTok Shop has become the most popular social commerce platform in Indonesia, with 45% of Indonesians using it to shop. However, because of the large number of TikTok Shop users, this has resulted in an increase in impulse buying which has become a positive value for the company from China. TikTok is widely used by teenagers aged 10-25 years. At this age, it is very suitable to be a marketing target for the products being promoted. The most popular products on TikTok Shop are fashion products. Several factors that encourage impulse buying at TikTok Shop are consumer character and lifestyle, price perception, motivation, promotions, discounts, and positive emotions that influence spontaneous purchasing decisions. The influence of promotions and preference purchasing motivation can influence customer impulse buying behavior and will lead to customer loyalty. This research aims to determine whether there is a significant influence on sales promotion and hedonic shopping motivation of fashion product buyers on impulse buying behavior which can have an impact on customer loyalty and a simultaneous influence between these variables on buyers in the Tiktok Shop marketplace. Research Methodology: Quantitative method used in this study with individual analysis units, data collection was done through a questionnaire with a valid sample of 400 respondents. Data analysis techniques use the Structural Equation Model (SEM) and Partial Least Squares (PLS) using the SmartPLS 4.0 application.