A clock 12-scale preparation fixture comprises an upper installation component and a lower installation component. The upper installation component and the lower installation component are each equipped with 12 spoke-type handles which are uniformly distributed at intervals along the circumference. When the upper installation component and the lower installation component are aligned and folded in the up-down direction, the 12 pairs of handles are folded correspondingly to fix an annular clock frame on which scales are to be made, the 12 pairs of handles block 12 section areas which are uniformly distributed at intervals on the annular clock frame, and 12 scale areas on the annular clock frame which are alternated with the 12 section areas are exposed and are used for being colored to form 12 scales. A clock 12-scale preparation method employing the fixture is further disclosed. By using the preparation fixture of the invention, the procedures are simple both for coloring the clock scales with a single color and coloring the clock scales with multiple colors, and the spacing precision and separating precision between colors are very high.