The bottom lining machine is composed of four parts: feeding machine, spreading machine, smoothing machine and noodle rack. The feeding machine is placed on the canal slope, the frame is connected with the frame of the spreading machine, and there are walking wheels at the bottom of the frame. The spreading machine, troweling machine and noodle rack are placed in parallel at the bottom of the canal, keeping a certain distance in the middle. The materials are put into the hopper of the loading machine by the tank truck, and then fed into the hopper of the spreader along with the belt, and then fed along the belt of the spreader. Evenly, after being smoothed by a smoothing machine, the noodle rack is manually closed.