Wall surface painting device for building decoration

The utility model discloses a wall painting device for building decoration, which comprises a base, a storage box, a lifting mechanism, a discharge mechanism and a painting mechanism, a stirring mechanism is arranged in the storage box and comprises a stirring shaft and a spiral stirring blade, the bottom end of the stirring shaft is in transmission connection with any one of the axles through a transmission mechanism, and the bottom end of the stirring shaft is in transmission connection with the spiral stirring blade. The discharging mechanism comprises a discharging bin fixed to the side wall of the storage box, a piston plate and a piston rod, a sliding rod is fixed to the other end of a piston, and the sliding rod is connected with the stirring shaft through a linkage mechanism; the coating mechanism is arranged on the lifting mechanism, the coating mechanism comprises a fixing plate, a mounting plate and a coating roller, the linkage mechanism is matched with the transmission mechanism in the process of