Abstract: With the large-scale integration of distributed renewable energy, the uncertainty and complexity of distribution network operation have significantly increased, making traditional planning approaches inadequate to meet the demands for high flexibility and reliability. To address this issue, this paper proposes a data-driven collaborative planning method for source-grid-storage in distribution networks. A coordinated model incorporating forecasting correction, flexible energy storage regulation, and a voltage risk index is constructed, upon which a multi-objective optimization framework and adaptive scenario weighting mechanism are established to achieve coordinated optimization of economy and security across multiple scenarios and time scales. Finally, simulation studies based on the improved IEEE 33-bus system validate the effectiveness of the proposed method, demonstrating its capability to reduce operational costs, minimize network losses, enhance voltage stability, and improve renewable energy accommodation.