This research investigates the relationships between the planning process of international joint ventures (IJVs) and the instability of IJVs, We recognize three important features of the planning process: the planning period, the comprehensiveness of planning process, and the levels engaged in planning. The event history analysis method is adopted to scrutinize the age distribution of instability of IJVs. Results show that the comprehensiveness of planning process is negatively associated with instability of IJVs. As for the insignificant parts of the results, this article also offers possible explanations that could be the base of the future research.