This comparative study was an attempt to analyze corporate social responsibility (CSR) disclosure practices of Hong Kong and mainland Chinese listed companies against economic, social and environmental dimensions (triple bottom line). In addition, the level and trend of disclosure practices were compared to provide a deeper understanding of the challenges of CSR development in these companies. The study was designed to employ qualitative analysis of the annual financial reports and the stand-alone CSR reports for the fiscal year ended 2009. Content analysis of CSR components of 16 leading companies listed in Hong Kong and China across eight industries was conducted. Findings from the study revealed that most of the Chinese companies caught up the trend of issuing separate stand-alone CSR reports, while most of the Hong Kong companies integrated the CSR sections into their financial reports. Further, several CSR practices and industry features were found aligning toward the triple bottom line. Although both Hong Kong and Chinese companies have proven to be making efforts in CSR reporting, different challenges and variations were found in the rapid growth of CSR development. Interestingly, none of the eight Chinese companies were selected as members of global sustainability indices. Overall, Chinese companies lagged behind Hong Kong companies in CSR reporting, especially with a lack of international perspectives and the neglect in negative responses of feedback and complaints from stakeholders. As the initial stage of CSR development in Hong Kong and China, there is still much progress needed to move toward international standards. Also, the companies should pay attention to increase the creditability and comparability of CSR reporting by adopting systematic standards as well as third party verification.