The disclosed method for producing a microstructure can form a complicated three-dimensionally formed microstructure with few steps.A first mask pattern (22) containing a light transmitting section and a light blocking section is disposed along an unexposed photosensitive resin (42), and a second mask pattern (32) containing a light transmitting section and a light blocking section is disposed on the reverse side of the first mask pattern (22) from the photosensitive resin (42). Additionally, by means of integrally rotating the photosensitive resin (42) and the first mask pattern (22) around a central axis (Z) that passes through the photosensitive resin (42) and the first mask pattern (22), and at the same time radiating exposure light from the reverse side of the second mask pattern (32) from the photosensitive resin (42) and the first mask pattern (22) in a direction that is inclined obliquely with respect to the direction of the central axis (Z), the light beam of the exposure light that is transmitted through the light transmitting section of the second mask pattern (32) and the light transmitting section of the first mask pattern (22) exposes the photosensitive resin (42).