The present study aims to compare Teachers’ Professional Development (TPD) between Mainland China and Hong Kong, by addressing the following questions: how do different social-cultural and historical contexts impact policy making of TPD in two regions; what similarities and differences referring to policies on TPD have been made in Mainland China and Hong Kong; how do the two regions implement TPD individually in terms of models/approaches, including categories, bases/partnerships, responsibility system, financial resources, training content, length of time, technological support; and what experiences of TPD do teachers both from Mainland China and Hong Kong have in practice; what do they think of the experiences; from their perspective, what are the limitations or problems of current practices?A qualitative research strategy, based on principles of comparative design and multiple-case study, was utilized for the study. And data were collected from document analysis and interviews. Individual semi-structured interviews were conducted among 16 teachers totally both in Mainland China and Hong Kong. The collected data were analyzed under focus questions and themes identified in the reviewed literature.The fingdings show that social, economical, political and cultural factors have contributed to shaping the features of TPD in the two regions and have accounted for the similarities and differences identified in the study, in terms of policy making, implementations of TPD, and teachers’ experiences as well as problems of TPD. Moreover, the study found that although each region had its strengths in TPD, it also had its weaknesses and aspects that need improvement. Hence, what we shoud do in one region is not to indiscriminately copy the other’s successful practices but to learn lessons from the other and find out effective ways that suit own circumstances.