An information processing device communicates with a block set assembled by a user, and thereby obtains information on the structure of the block set. In addition, a corresponding position setting screen including an image of an object corresponding to the block set is displayed on a display device. The user moves a joint of the block set which joint is desired to be associated, by for example bending and stretching the joint. Next, the user indicates a joint to be associated on a 3D object side in the image of the 3D object by a cursor, and performs a determination input. The joint of the block set and the joint of the 3D object are thereby associated with each other. The block set and the object are interlocked with each other bidirectionally by thus setting the corresponding positions of the block set and the object.
