The fashion business and society at large are profoundly affected by the interplay between consumer behaviour and fashion trends. The purpose of this study paper is to examine the mental processes that govern buying habits and the latest fashion trends in the hopes of better understanding the forces at work in this industry. This research delves into the psychological processes that influence how people perceive, feel about, and act in relation to fashion, drawing on ideas and concepts from marketing, sociology, and psychology. The study delves into the intricate web of elements that contribute to the rise and fall of fashion trends, including the impact of social conventions and cultural influences, as well as the psychological processes of self-expression and identity development. In addition, the study delves into how consumers' social identities, self-esteem, body image, and personality attributes influence their fashion-related decisions. The fashion industry and its marketers may improve their methods for reaching and interacting with consumers by delving into the mental processes that influence purchasing decisions. In addition, the study delves into how social media and technology impact fashion trends and customer behaviour, drawing attention to the impact of online platforms on the spread of trends, the agency of consumers, and the level of connection with brands.