A method of forming a mask pattern and, more particularly, a method of forming a mask pattern wherein micro patterns having resolutions lower than those of exposure equipment by overcoming the resolutions of the exposure equipment, wherein, a silicon layer is formed over a substrate and is patterned. The patterned silicon layer is oxidized to form the entire surface of the silicon layer to a specific thickness by using an oxide layer. The oxide layer is removed to expose a top surface of the silicon layer. A mask pattern is formed with the remaining oxide layer by removing the silicon layer.