To provide a block product and a structure of the block product made of ceramics or plastics, having a dowel provided with a hard ceramic dowel core body and a cushioning packing, and elliptic dowel holes, reduced in weight by providing a space part inside a block, assembled with simple operation and completed by applying an adhesive sealing material or an adhesive caulking material to joint grooves positioned at an outer end part, a center part, a plane (an upper face) and a side face of each block after assembly.

Each block 1 is provided with the dowel holes 2 in vertical symmetry. To connect each block 1, the lower half of the dowel 5 with the cushioning packing 4 fitted to the hard ceramic dowel core body 3 is fitted into the dowel hole 2 of the lower block 1, and then the cushioning packing 4 is fitted into the dowel hole 2 of the upper block 1. The dowel core body 3 fitted into the lower block 1 first is put over and pressed to connect and fix the upper and lower blocks 1. The adhesive sealing material or caulking material is fitted to the joint grooves 6 at the end part, center plane (upper face) and side face of each block 1 formed into the desired structure for completion.