Background. Under the "two countries, one system" policy implemented by China to manage the return of Hong Kong's sovereignty, Hong Kong has maintained a comparatively prosperous economy within the Asian region. This has resulted in an environment which fosters migration from the mainland to Hong Kong, due largely to proximity, higher earning potential, common language, and a relaxing of border control measures. However not all mainland China citizens are equally able to access these new migration schemes and indeed a number of women such as sex workers are either migrating and/or working illegally and without occupational, legal and health protection within Hong Kong. Discussion. Female migrant sex workers are exposed to a number of significant threats to their health, however their illegal status contributes to even greater vulnerability. The prevailing discourses which view these women as either "trafficked women" or as "illegal immigrants" do not adequately account for the complex situations which result in such women's employment in Hong Kong's sex industry. Rather, their position can best be understood within the broader frameworks provided by migration literature and the concept of "structural violence". This allows for a greater understanding of the socio-political issues which are systematically denying migrant sex workers adequate access to health care and other opportunities for social advancement. When these issues are taken into account, it becomes clear that the current relevant legislation regarding both immigration and sex work is perpetuating the marginalised and vulnerable status of migrant sex workers. Unless changes are made, structural barriers will remain in place which impede the ability of migrant sex workers to manage their own health needs and status. Conclusion. Female migrant sex workers in Hong Kong are extremely vulnerable to a number of occupational health and safety hazards which have significantly detrimental effects on their health. These risks can best be understood within a broad framework of socio-political factors contributing to their vulnerability. Ensuring that migrant sex workers have adequate support for their health and legal rights requires require structural interventions such as decriminalisation and providing open and inclusive access to health service to counteract such factors.