With the increasing of press’ speed and the people’s requirement, online testing of printed stock becomes to the development direction. The ink metering control is an important part of printing quality control. So this paper sets up a three-dimensional curved surface model of the CCD’s RGB values and the best ink film thicknesses based on Calabro-Mercatucci model, which can be applied to the online ink testing with CCD. Firstly, we printed cyan magenta yellow black color bitches of different ink film thicknesses and got their optical densities and RGB values with measuring tools. Afterwards, we got the parameters in Calabro-Mercatucci model with the experimental data through the least square algorithm and then got the scale of the best ink film thickness. Last, we set up the three-dimensional curved surface model of the CCD’s RGB values and the best ink film thicknesses through ‘v4’ algorithm in matlab tools. With this three-dimensional curved surface model, we can judge whether the thickness corresponding to the RGB values is in the range of the best ink film thickness. It is proved that this method can indicate the relationship between CCD’s RGB values and the ink film thickness and be applied to detect the ink metering after tested.