A micro-grooving method by ultrasonic machining with a lamination tool has been devised. Thin walls on the tip of an ultrasonic tool can fabricate many grooves on a workpiece by one ultrasonic-machining process. Thinner wall for fabricating micro grooves, however, poses the lack of the stiffness of the tool, resulting in the difficulty of the grooving. Then the walls are enfolded with a soft material such as a polymer plastic to supplement the lack of the stiffness. Since soft material absorbs the energy of the ultrasonic vibration, the damage by the impacts of the abrasive particle on the workpiece surface under the soft material is little. Therefore multiple micro-grooves can fabricate efficiently by using of a lamination tool in which thin hard-materials and thin soft-materials are laminated alternately. In this paper, the lamination tools were developed with a thin shim-sheet as the hard material and an epoxy adhesive as the soft material. The fabrication experiments of the parallel grooves on alumina ceramics were conducted. This paper investigates the influences of the parameters of ultrasonic machining such as the grain size of the abrasive particle, the static machining load or static normal stress applied to the tool-workpiece contact region and the grooving time upon the characteristics of the micro-grooves. The results show that the grooving efficiency depends on the grooving time and the static normal stress. Finally, some applications are shown.