Abstract: An automatic cleaning device for use on a stock farm, including an automatic switching system, a transmission case, a sprinkling system and a water pump. The automatic switching system utilizes water pressure to push a valve seat so as to achieve an automatically switching effect without using electric power. By means of a splined circular rod, a first and a second rotary rods and a one-way bearing in the transmission case in cooperation with a linking lever and connecting arch block of the sprinkling system, a linear movement of a slidable piston is converted into a speeded up and down pivoting and left and right swinging movement of a sprinkling head of the sprinkling system. A flow controlling mechanism of a hydraulic means is used to achieve alternate fast and slow cleaning operation of the sprinkling system. By means of changing pivot holes of a connecting block for pivotally connecting with the linking lever, a starting point of the sprinkling head is adjustable.