The method for producing a pillar-shaped semiconductor device includes a step of providing a structure that includes, on an i layer substrate, a Si pillar and an impurity region located in a lower portion of the Si pillar and serving as a source or a drain, a step of forming a SiO2 layer that extends in a horizontal direction and is connected to an entire periphery of the impurity region in plan view, a step of forming a SiO2 layer on the SiO2 layer such that the SiO2 layer surrounds the Si pillar in plan view, a step of forming a resist layer that is partly connected to the SiO2 layer in plan view, and a step of forming a SiO2 layer by etching the SiO2 layer below the SiO2 layer and the resist layer using the SiO2 layer and the resist layer as masks.