The invention relates to a paving device and especially relates to a cobblestone paving device applicable to a building. The invention solves the technical problem and provides the cobblestone paving device applicable to the building. The device is good in paving effect, high in paving efficiency and manpower-saving, The cobblestone paving device applicable to the building comprises a base, wheels, a pushing handle, a box, a valve, a first cylinder, a pushing board, a baffle, a connection board, a slideway, a first support bar, a second cylinder, a sliding block, a first rack, a spring, a gear, a second support bar, a second rack and a fattening device. The wheels are arranged at the bottom of the base, the pushing handle and the box are arranged at the upper part of the base, the pushing handle is positioned on the left of the box, an outlet is formed in the bottom at the right in the box, the valve is arranged at the middle of the outlet, the spring is connected between the left section of the valve and the right section of the base, and the first cylinder is arranged on the inner wall of the left of the box. The cobblestone paving device applicable to the building achieves the effects of being good in paving effect, high in paving efficiency and manpower-saving.