Ratione temporis means that the arbitral tribunal has jurisdiction over the disputes arising from the time of occurrence. The ICSID Convention does not directly stipulate that the temporal clause in the investment agreement and the principle of general international law are the main basis for determining the ratione temporis of disputes. The judgment criteria of ratione temporis used in different investment agreements are different and the different understanding of the judgment criteria established by the temporal clause is an important source of the dispute of time jurisdiction. The application of the principle of non-retroactivity and the principle of interpretation is another reason for the dispute of ratione temporis when the temporal clause is missing or the meaning is unclear. In practice, the application of laws on investment arbitration jurisdiction disputes has not been unified. Under the influence of the value orientation of expanding jurisdiction, arbitration tribunals adopt different interpretation methods, resulting in opposing awards, which aggravates the situation of ratione temporis jurisdiction disputes. Since the arbitration tribunal still takes the investment agreement as the main adjudication basis, perfecting the temporal clause is the main way to avoid and resolve the dispute ofratione temporis.