The invention relates to a gas storage rock salt sample preparation device, and mainly solves the problem that the yield is extremely low as a core of a crisp hard porous material is not easily cut by an existing core cutting device. The gas storage rock salt sample preparation device is characterized in that a vertical slide rail (3) is arranged in an upright (1), a crank block (4) is connected onto the slide rail (3), a C-shaped support arm (2) is connected onto the crank block (4), a cutting line (5) is connected between two end points of the support arm (2) through a locking screw (6), support columns (11) are fixed at the upper part of a rack (13), cross beams (12) are fixed at the upper parts of the support columns (11), the upper parts of the cross beams (12) are connected with a moving guiderail (14) through a T-shaped groove, and a core sample to be cut is fixed at the upper part of the moving guiderail (14) through clamps. The gas storage rock salt sample preparation device can cut core samples made of various materials and in various shapes, is particularly suitable for the crisp hard porous material, and is high in yield.