[Purpose/significance] Social media data has become an important data source in academic research. However, scholars often ignore the ethical risks in collecting and using social media data. This study analyzes the research on social media data from the ethical perspective, and reminds researchers to better understand the research methods and ethical challenges faced by such research. [Method/process] Taking Sina Microblog as the research object, this paper makes ethical reflection on microblog data research from four perspectives, researchers lack data ethics awareness; unclear definition of public and private data; microblog data research lacks scientific informed consent mechanism; the normative nature needs to be strengthened. [Result/conclusion] Ethical norms, that is, through effective regulation, ensure that all aspects of research are in the ethical space. Microblog contains a lot of personal data, and the development and evolution of microblog data research also has a strong demand for ethical norms. This study suggests that, we should establish the data education system to enhance the awareness of "data ethics", and the researchers cannot assume the consent of users. We should explore a scientific informed consent machine, encourage cross field cooperation, and balance the innovation and risks.