Sliced specimens can be automatically and continuously prepared and burdens of an operator can be reduced while accuracy required for the sliced specimen is maintained. The sliced specimen is prepared by relatively moving a specimen block transfer section and a cutter, and when a slicing operation to adjust the height position of the specimen block is continuously performed so that the cutting surface of the specimen block is located at a sliceable position, the cutter is moved so that a contacting area of a blade edge of the cutter that firstly contacts the specimen block after the height position adjustment is sequentially changed, every time previously set number of times of slicing operation is completed. Thereafter, the height position of the blade edge of the cutter after the change is measured by a detector, and based on the measurement information of the detector, the sliceable position is corrected and the slicing operation is resumed.