To prepare a sliced specimen with its shape kept, from a sample including a soft tissue, a hard tissue, a cartilage tissue and an adipose tissue in a short time.

The method for preparing the sliced specimen in a short time includes: putting a sample piece of a biological tissue into a metal container filled with a water-soluble gel; forming a hole through which the water-soluble gel expanded by freezing flows on a surface in contact with the water-soluble gel of the metal container; placing a metal sample holder of a freezing microtome formed by filling flexible foam into the hole on the metal container, so that the water-soluble gel in the vicinity of the hole is finally frozen; sinking the metal container in coolant to freeze the sample piece of the biological tissue and the water-soluble gel; taking out the frozen sample in a state where the frozen sample piece of the biological tissue, the frozen water-soluble gel and the sample holder of the freezing microtome are integrated with each other, from the metal container; mounting the taken-out frozen sample on the freezing microtome; and thereby preparing the sliced specimen.