The invention discloses a dust-free crushing device for construction waste treatment. The device comprises a base, a device main body, a feeding bin, a feeding opening and a discharging opening, wherein the device main body is connected to the middle of the base, a reserved opening is formed in the middle of the upper portion of the device main body, the feeding opening is formed in the left sideof the upper portion of the device main body, a feeding pipeline is connected to the upper portion of the feeding opening, a second conveying belt is arranged between two second rolling rollers, and the top end of the left side of the second conveying belt is arranged at the position, close to the right side, of the upper portion of the discharging opening. According to the dust-free crushing device for construction waste treatment, dust removal work can be carried out at the positions of the feeding opening and the discharging opening of the whole device, the whole device cannot be blocked inthe feeding and crushing processes, the influence, from the process of using the whole device, on the environment is small, the fault occurrence rate of the whole device during working is low, and the dust-free crushing device is more convenient to use and operate.