The work aims to solve the problems regarding on the gray balance data reproduction under specific process conditions. The tone reproduction curves about cyan, magenta, yellow and black under certain process condition were acquired and the curve equations were fitted. The dot area coverage of cyan, magenta and yellow under the same density (theoretical density) were calculated according to the equations. After that, the sample color blocks were further designed based on the obtained dot area coverage and their corresponding chromatic value and density value (actual density) were measured. The results demonstrated that the chromatic value of the designed color blocks was estimated to be 0, which confirmed the neutral gray property of these studied color blocks. Therefore, a mathematical model between the theoretical density value and the actual density value was established, followed by combining the model with color tone reproduction curve equation, hence the parameter data of gray balance under the certain process condition was obtained. This work not only provides a possible way for obtaining the gray balance data under specific process condition, but also offers a theoretical reference for the corresponding digitization modeling of gray balance data.