A method is provided for making a micromirror unit which includes a frame, a mirror forming base, and bridges connecting the frame to the mirror forming base. The method includes the following steps. First, a first mask pattern is formed on a substrate for masking portions of the substrate which are processed into the frame and the mirror forming base. Then, a second mask pattern is formed on the substrate for masking portions of the substrate which are processed into the bridges. Then, the substrate is subjected to a first etching process with the first and the second mask patterns present as masking means. Then, the second mask pattern is removed selectively. Then, the substrate is subjected to a second etching process with the first mask pattern present as masking means. Finally, the first mask pattern is removed.