This study investigated the social identity and sense of belonging of a small group of Macau-born Portuguese citizens who identified themselves as people of Macau (and Macanese) with Portuguese citizenship who have relocated to Portugal, the legal homeland from a legal perspective. Through a qualitative method using the general inductive approach with the thematic design together with the social identity theory as the theoretical framework, this study addressed two research questions, including (1) How do first-generation Macau-born people of Macau (and Macanese) with full Portuguese citizenship describe and make sense of their multiple social identities after relocating to Portugal, and (2) What challenges, experiences, and stories do Macau-born people of Macau (and Macanese) with full Portuguese citizenships experience in establishing their sense of belonging between Macau and Portuguese societies? Based on the semi-structured interview and remarkable item sharing tools, three families with 14 participants were invited to join this study. Three main themes were categorized, including (1) social categorization in the postcolonial environments, (2) the conflicts and negotiations of social identification, and (3) the relationships between social comparison and positive distinctiveness. The results of this study will fill the research gaps in the fields and areas of social identity, sense of belonging, and challenges of individuals and groups from Portuguese former and overseas colonies and territories who are living in continental Portugal for long-term development. Moreover, the outcome of this study offers future research directions for researchers to investigate furthert he contemporary challenges and social issues of immigrants into Portugal.