An etching method includes loading, first and second supplying, removing and etching steps. In the loading step, a target object is loaded into a chamber. In the first supply step, a first gas containing carbon, hydrogen and fluorine is supplied into the chamber. In the modification step, plasma of the first gas is generated to modify a surface of a mask film and a surface of an organic film which is not covered with the mask film. In the second supply step, a second gas for etching the organic film is supplied into the chamber. In the removal step, a modified layer formed on the surface of the organic film is removed by applying a first high frequency bias power. In the etching step, the organic film below the modified layer is etched by applying a second high frequency bias power lower than the first high frequency bias power.