Anisotropic Sm 2 Co 17 flakes with high aspect ratio were prepared by magnetic field assisted high energy ball milling in the presence of heptane and oleic acid (OA). The thickness of flakes was only tens of nanometers. Coercivity of 3 kOe was achieved in the nano-flakes. Most interestingly, the magnetic crystalline anisotropy of Sm 2 Co 17 flakes was improved compared to that of particles made by traditional ball milling. These anisotropic Sm 2 Co 17 nano-flakes could be the building blocks for the future high-performance nano-composite permanent magnets with an enhanced energy product.