This research explores the impact of relational benefits, which are the advantages gained from a sustained relationship with a specific brand, on switching barriers and brand loyalty among female consumers aged 20 to 50 residing in China when purchasing luxury cosmetics. The research analyzes the influence difference between different retail formats online and offline, aiming to reveal the shifting psychological dynamics of consumers amid the latest changes in China's consumer market. Using SPSS and AMOS programs, data from 500 participants were analyzed, with a focus on seven types of relational benefits: experiential benefits, confidence benefits, special treatment benefits, convenience benefits, economic benefits, information benefits and risk reduction benefits. The results indicate that relational benefits significantly enhance switching barriers and brand loyalty, and these effects vary distinctly between online and offline retail channels. The findings offer valuable insights for luxury cosmetic brands to formulate effective strategies in the Chinese market.