Disclosed is a method of forming a pattern. A first organic polymer layer is formed on a substrate on which an underlying layer, and then a second organic polymer layer, which has an opening partially exposing the first organic polymer layer, is formed on the first organic polymer layer. Next, a silicon-containing polymer layer is formed on the second organic polymer layer to cover the opening. The silicon-containing polymer layer is oxidized and simultaneously the second organic polymer layer and the first organic polymer layer are ashed by oxygen plasma to form a pattern having an anisotropy-shape. The underlying layer is etched using the silicon-containing polymer layer and the first organic polymer layer as an etching mask to form a pattern.