Like that mentioned in the 2nd report, because of panel`s sense of psychological and physiological responsibility caused by multi-samples, great errors in experimental results are expected. So as to cut down these errors, the new method called $quot;Pair Comparision with Standard$quot; that reduces test frequency and is superior in detecting power is designed, and its mathematical model is proposed. This paper suggests that this method can be used for screening test that, first of all, selects 4-5 of multi-samples and the most efficient sensory evaluation method in laboratorial quality study is that, after screening by this method, Trio Paired Comparison for the final justification is applicated.