This dissertation explains whether the rule of law in Hong Kong is at stake under the sovereignty of China and, if so, how did lawyers defend the rule of law in post-movement Hong Kong. This dissertation creates the concepts of ‘authoritarian legal transplant’ and ‘legal resistance’ to answer the questions above. Hong Kong’s rule of law, inherited from British colonialism, has evolved incrementally towards convergence with China’s authoritarianism because of the impacts of authoritarian legal transplants on Hong Kong’s legal system and professional legal culture. China’s united front strategy had made the domestic legal profession more politicised than before and succeeded in consolidating ‘comprador professionalism’, referring to lawyers being economically driven to assist the authoritarian state to consolidate its ‘rule by law’ project. However, the conflicts between the authoritarian project and the liberal understanding of the rule of law in Hong Kong have generated resistance from the legal profession. This dissertation proposes three strategies as forms of legal professionalism to explain legal resistance. They are ‘confrontational professionalism’, ‘democratic professionalism’ and ‘resistant professionalism’, indicating different approaches by members of the legal professional bodies and activist lawyers to strengthen civil society to defend the rule of law institutions, civil liberties and a liberal rule of law culture against threats from authoritarian legal transplants. These forms of legal resistance played essential roles in resisting the state’s encroachment on Hong Kong’s rule of law between 2014 and 2020. This dissertation offers a theoretical study of whether and how the rule of law can be preserved in authoritarian and semi-authoritarian regimes. It also provides a micro account of the rule of law in Hong Kong by examining the actions and practices of lawyers against authoritarian rule, and sheds light on the understanding of China’s expansion of its political and legal influences beyond its jurisdiction today.