Abstract: As China gradually increase the gap between supply and demand of iron, the pace of iron foreign investment is gradually increasing, and the question of the investment risk comes into focus. Based on the theory of mineral resources investment and risk assessment, this paper first ascertained the layer index evaluating system affecting iron investment oversea by experts investigation, established the AHP-Fuzzy model by the method of combing AHP and Fuzzy in this paper. The evaluation model provides a quantitative method to judge investment risk oversea for investors, improves the investment decision-making. Taking an iron project in Western Australia as an example, the experimental results indicate that the grey fuzzy synthetically evaluation method is a more effective method for risk analysis of iron investment oversea.