Entrepreneurship has been widely adopted as a policy to support migrants, yet the focus on its economic benefits has overshadowed its socio-cultural impacts. This dissertation, drawing on acculturation theory and social identity theory, explores the effects of being an entrepreneur on the identity reconstruction of post-2019 Hong Kong (HK) migrants in the UK. While existing literature often portrays identity as a static concept that founders draw upon to shape their ventures, this study argues that there is a reciprocal relationship between entrepreneurship and identity. Through semi-structured interviews with 12 HK migrant entrepreneurs and participant observation at three cultural festivals, it is found that while their ventures are influenced by multiple identities, including whether they identify more as Hongkongers or British, entrepreneurship also serves as a sociocultural learning process for migrants to construct their new identity. This occurs typically through three mechanisms: (i) relationship building, (ii) emotional attachment and (iii) customer feedback. Additionally, the findings suggest that entrepreneurship empowers migrants to enact their agency and mitigate acculturative stress, eventually improving their overall well-being. This study contributes to the fields of entrepreneurship and migrant studies in three key ways: first, it emphasises the reciprocal nature of the relationship between entrepreneurship and migrant identity construction; second, it broadens the understanding of migrant entrepreneurship by focusing on its socio-cultural, not just economic, outcomes; and third, it provides empirical evidence of how post-2019 HK migrants redefine their identity through entrepreneurship, offering valuable insights for future research on migrant entrepreneurship and the evolving identity of the HK diaspora.