Three geochemical prospecting techniques, i. e., geochemical stream sediment survey, soil survey and rock survey, have been conducted experimentally in two 1:50,000 map areas of southwest Yunnan, and a comparison of these three geochemical methods in the light of their ore prospecting and economic results leads to the conclusion that they have quite similar ore prospecting effects. Nevertheless, the stream sediment survey is obviously better than the soil survey in that it has high contrast for anomaly, less field work for sampling and is comparatively inexpensive in sample analysis. Another conclusion the author has reached in the test is that geochemical rock survey carried out at sparse survey grid, e.g.,approximately two samples for each square kilomreter,can attain fairly satisfactory result in obtaining information of anomalies and understanding regional variation regularity of the distribution of minor elements. Therefore, as an effective regional geochemical prospecting technique, rock survey deserves due attention and further research.