Establishment of causality between drug exposure and adverse event, namely adverse drug reaction (ADR) assessment, is a crucial procedure in drug safety evaluation. While various causality assessment tools for ADR have been published, the poor agreement among them hinders the collection, analysis and interchange of drug safety data, and causes confusion for ADR research as well. The correlation of safety information throughout the whole process of clinical trials is important, so it is well-advised to maintain causality assessment criteria as coherent and consistent in both pre-marketing and post-marketing stages. Furthermore, the application of the WHO-UMC and ICH causality assessment system may promote ADR causality assessment standardization. Since joining the ICH, China has developed a series of regulations and guidelines on ADR monitoring and evaluation. However, these documents remain unclear towards the operating instructions for ADR assessment, especially in the early pre-marketing stages. Accordingly, we suggest that coordinated and consistent causality assessment criteria and relevant operating instructions be developed to improve the data sharing and continuity of drug safety monitoring in China.