Basically, there are two ways viewing the reservoir storage-yield relationship., The most common viewpoint is the determination of the storage required at a given reservoir to supply a required yield. This type of problem is usually encountered in the planning and early design phases of a reservoir. The second viewpoint is the determination of yield from a given amount of storage. This often occurs in the final design phases or in re-evaluation of an existing reservoir for a more comprehensive analysis. The purpose of this study is to improve the present methodology estimating the storage-yield relationship for a reservoir design or a reservoir operation. The Residual Mass curve Technique, the slightly modified version of Low Flow Techniques and the Transition Probability Matrix Technique are reviewed and examined for the best fit technique to find the reservoir storage-yield realtionship. The historical data during 1917~1940 at the proposed Hongchun damsite and the synthetic data simulated by Thomas-Fiering model are utilized to examine the reservoir storge-yield relationship with three techniques in detail. After the three techniques which estimate the reservoir storage-yield relationship were reviewed extensively, it was concluded that the Residual Mass Curve Technique and the slightly modified version of Low Flow Techniques were suitable for a preliminary design, but the Transition Probability Matrix Technique Provided satisfactory results as a final design technique because it reflected the variation of a monthly yield as well as seasonlly.