Academic marketing scholars have paid considerable attention to the green purchasing intention of fashion products. From the perspective of transition countries, research on environmental awareness and consumers' attitude toward green purchasing is extremely limited, particularly for fashion products. The purpose of this study is to examine the factors that influence the green purchase intention of fashion products from the perspective of Vietnam, a transition country. This study used an integrated research model by combining the Value Identity Personal Norm Model and the Theory of Planned Behavior. This model was used to determine how Vietnamese consumers plan to buy green products in the fashion industry. Notably, personal norms and the attitudes of consumers are two mediators in the research model. To collect data, a self-administered questionnaire survey was conducted in the three largest cities in Vietnam. Three hundred and forty-eight valid responses were analyzed using the SmartPLS 3.0 software for partial least squares structural equation modeling. Findings indicate that environmental self-identity and personal norms have a significant influence on attitude toward green fashion purchase intention. In turn, the strongest predictor of green purchase intention is the attitude, followed by subjective norms and perceived behavioral control. As a result, solutions are proposed for marketers and government bodies to change their approach to promoting green purchasing behavior in the Vietnamese apparel industry.