This study introduces 5 methods of causality assessment of adverse drug reactions (ADRs) domestic and overseas. According to the assessment of ministry of public health of China, the key points about the relevance analysis have been illuminated for the post-evaluation of Chinese patent medicine. Under the guidance of the causality assessment, we should describe the ADR reports in detail and further detect the accurate ADR warning signals. In order to supplement the ADR information, more researches concerning the ADR mechanism should be fully explored.