Abstract: To reduce the risk of mining investment in foreign countries, based on matter-element model theory, extension set theory and dependent function calculation, an extension assessment model for the mining investment environment in foreign countries was established using matter-element analysis theory, converting the qualitative appraisal into a quantitative one.The assessment of the mining investment environment in Vietnam, Thailand, Laos and Burma surrounding Yunnan was made using this model, which indicates that the mining investment environment of these four countries are ranked in the order of “good, good, general and general” correspondingly.

Key words: Assessment of mining investment environment in foreign countries, Extenics theory, Matter-element theory