The construction of self, a fundamental process for development. Twins, as they grow together, may encounter greater difficulties in individuation process. The present study aims to investigate the construction of the image of the self and of the self with its own twin/sibling through the drawing of the human figure and to highlight any differences in these representations between monozygotic twins, dizygotic twins, and non-twins. A sample of 105 children aged between 4 and 6 years participated in the research. From the analysis of the drawings of the self and of the self with the sibling, differences in self-representation and representation with the sibling have emerged and can be understood in the light of the separation and individuation process that characterizes the development of the self-image. In particular, greater tendencies have emerged for monozygotic twins to represent themselves differently from the co-twin and for dizygotic twins to show identical figures.