A three-dimensional (3D) microstructure fabrication technique utilizing hard x-ray lithography has been developed. In this technique, as the intensity distribution of the x rays is controlled by a newly developed bending mirror, the exposure residual depth of polymethylmethacrylate (PMMA) resist is controlled over the exposed area. The maximum difference of depths was approximately 50 μm over the large area more than 60 mm (horizontal)×5 mm (vertical). We also investigated the effects of controlling the beam intensity distribution on the obtained 3D resist pattern shapes by changing x-ray mask absorber shapes and angle. 3D PMMA patterns with inclined shape sidewall and graded depths were successfully fabricated. We believe this technique greatly expands applications of the LIGA process.