The invention discloses a method for detecting and controlling a material level and a system for detecting and controlling the material level. The method comprises steps of receiving the image information of the number of pump materials in a representation hopper, which is acquired by an image sensor; identifying the changing trend of the number of pump materials in the hopper in accordance with the image information of the number of pump materials in the representation hopper; and sending control signals in accordance with the changing trend of the number of pump materials and changing the mixer truck discharging speed and/or the pump material conveying device pump material speed. The method and the system are not monitored through manual operation, the labor intensity and the labor cost are greatly reduced, the control process is simple and the implementation is easy.