A building blocks that can be easily assembled or disassembled, comprising a building block main body. Each side of the building block main body is configured with a connecting structure. A plurality of building block main bodies is joined together through the connecting structures. The connecting structure comprises a connecting seat and a connecting rod. The connecting seat has an open connecting slot. The inner walls on the two sides of the open connecting slot are both formed with positioning bumps. The two sides of the connecting rod are respectively configured with a first and a second positioning slot. The two sides of the connecting rod are further configured with a first and a second guide slot that are respectively communicated to the first and the second positioning slot.