The invention relates to simplified designing of a testing die, in particular to a large skin part testing die which comprises a die body. The die body is of a frame structure, the upper side of the frame structure is a molded surface which is formed by a plurality of clamping boards, the lower portion of each clamping board is connected with the die body in a fastened manner, and the upper surfaces of the clamping boards jointly form a die molded surface which is matched with the shape of a skin part. Weight of the testing die is effectively reduced, and manufacturing cost is reduced; contact area of a large skin part and the testing die is reduced, convenience is brought to part testing, skin scratching and bruising probability is lowered, and surface weight of the skin part is increased.