It is intended to provide a method of producing a semiconductor device, comprising the steps of: providing a substrate on one side of which at least one semiconductor pillar stands; forming a first dielectric film to at least partially cover a surface of the at least one semiconductor pillar; forming a conductive film on the first dielectric film; removing by etching a portion of the conductive film located on a top surface and along an upper portion of a side surface of the semiconductor pillar; forming a protective film on at least a part of the top surface and the upper portion of the side surface of the semiconductor pillar; etching back the protective film to form a protective film-based sidewall on respective top surfaces of the conductive film and the first dielectric film each located along the side surface of the semiconductor pillar; forming a resist pattern for forming a gate line in such a manner that at least a portion of the resist pattern is formed on the top surface of the semiconductor pillar by applying a resist and using lithography; and partially removing by etching the conductive film using the resist pattern as a mask while protecting, by the protective film-based sidewall, the portions of the conductive film and the first dielectric film each located along the side surface of the semiconductor pillar, to form a gate electrode and a gate line extending from the gate electrode.