The present invention relates to the technical field of constructional engineering construction devices. Disclosed is an automatic stirring apparatus for constructional engineering. The automatic stirring apparatus comprises a housing. The upper end of the housing is fixedly connected to a motor, and an output end of the motor penetrates through the upper end of the housing and is fixedly connected to a second gear; the left and right ends of the second gear are engaged with first gears, intermittent gears are fixedly connected to the lower ends of the two first gears, and a rack is connected between the two intermittent gears in an engaging manner; a sliding hole is formed in the upper end of the rack, and a rotating shaft is fixedly connected to the lower end of the second gear and penetrates through the sliding hole; stirring blades are fixedly connected to the circumferential surface of the rotating shaft, first connecting rods are fixedly connected to the front end and the rear end of the rack, and a fixed frame is provided in the housing, so that a mixture can be finally stirred, stirring is more sufficient, stirring efficiency is improved, construction time is shortened, production cost is saved, and practicability is extremely high.