This paper tries to explain the conservation behaviour as one of the aspects of sustainable consumer behaviour. The theory of Values Beliefs Norms is chosen as the theoretical framework of this research. This theory discusses that the conservation behaviour is adopted owing to the activation of the personal norms by the values and the beliefs of individuals. A study of 703 individuals has been made in an attempt to test the model of this study. The data is analysed through the structural equations method. The results have enabled us to validate the VBN model in the Tunisian context.