To provide a case for preserving solid dairy products such as butter.
The preservation case has a mid underlay member set in a housing chamber of a case formed by detachably fitting an upper case body in a lower case body in a manner to take out the mid underlay member freely, and has a structure to accommodate the solid dairy product in the housing chamber while the solid dairy product is supported on a shelf board part of the mid underlay member. The solid dairy product is cut lengthwise and crosswise on the shelf board part formed on the mid underlay member with a cutting implement. The mid underlay member has lattice-shaped markers extending linearly at equally spaced intervals on the surface of the shelf board part and has supporting walls stood on both ends of the shelf board part. Each of the supporting walls is constituted of divided wall pieces, and the markers face the gaps formed between adjacent wall pieces.