High-speed cutting is a complexity and uncertainty process .The cutting parameters optimization is ambiguous. In this paper, based on the orthogonal experiment of high-speed milling aluminum alloy 7475, we use fuzzy comprehensive evaluation to optimize the parameters high-speed milling of aluminum alloy 7475 in the indication of surface roughness, cutting force, material removal rate. We have got cutting parameters optimal that is highly processing quality and productivity. Compared optimal results with orthogonal experimental results, we found that the optimal result is reliable. The study shows that fuzzy comprehensive evaluation method can optimize the parameters of high-speed milling of aluminum alloy 7475 accurately. This method has also a good application effect to other materials and great significance to guide actual production.