The invention discloses an oil-water metering instrument which comprises two parts of an oil-water meter and an image pick-up monitor, wherein the oil-water meter and the image pick-up monitor are matched to use; the oil-water meter comprises a pedestal, an upright column, a glass pipe and a scale plate, wherein the glass pipe and the scale plate are connected to the upright column, a liquid inlet pipe and a liquid outlet pipe are arranged at the lower end of the glass pipe, and the upright column is fixedly connected with the pedestal; the image pick-up monitor comprises an image pick-up device and a stand, wherein the stand is also provided with an operating device, a driving device and a lifting mechanism, the driving device is in driving connection with the lifting mechanism, the image pick-up device is fixedly connected with the lifting mechanism, and the operating device controls the driving device and the image pick-up device and is used for metering the oil-water liquid level on the oil-water meter; and the image pick-up device faces the direction of the glass pipe and the scale plate. The invention has accurate recording and can save external force.