Abstract: The present disclosure relates to a self-assembly block toy set in which each block interlocks with each other laterally, at right angles along the side of each of the blocks, vertically or in other various ways, thereby being assembled into diverse models. The self-assembly block toy set includes a plurality of square blocks, wherein the square block includes a main body unit that assumes the shape of a square prism with specific height, an interlocking unit that forms outside each side of the main body unit, a vertical interlocking protuberance or a vertical interlocking slot that forms on the top surface and the bottom surface of the main body unit, a cross axis inserting hole that forms at the center of the main body unit and a plurality of interlocking unit inserting holes that form in the main body unit except for the cross axis inserting hole.

Abstract: Disclosed herein is a block toy that has a magnet embedded inside and a surface structure for connecting a block thereof, wherein overhang-like structures and hollow-like structures are formed on the block surface of the block toy that has a magnet embedded inside so that the overhang-like structures on each block surface interlock organically with the hollow-like structures on each block surface in order to secure stable assembly between the blocks of a block toy when the blocks are stacked up or interlocking at right angles or laterally to each other, thereby, especially, preventing the block thus interlocked from slipping out of the assembly with the external force that is exerted in a direction other than the direction the block interlocks in when it is stacked up or interlocking at right angles or laterally with each other.