Encouraging the purchase of second-hand clothes is a viable strategy to reduce the negative consequences of the fashion industry. The research examines the second-hand clothing behavior of Vietnamese young customers based on their behavioral and psychological perspectives. The novelty of the study is that it expands and compensates for the limitation of the theory of planned behavior when explaining the purchase intention of second-hand clothing. A conceptual model linking different types of attitudes, subjective norms, perceived behavioral control, personal norms, psychological consequence, and purchase intention were tested upon 341 Vietnamese young customers. The results indicate that attitude towards the environment, attitude towards the purchase of second-hand clothing, subjective norms, and psychological consequences are significant determinants of the purchase intention of second-hand clothing. Moreover, demographic characteristics such as age, gender, income, and experience in purchasing second-hand clothes also influence the purchase intention. These research findings provide valuable implications about useful marketing strategies to encourage second-hand clothing consumption – as a green behavior among young people.