The work aims to study the effects of key parameters on the printing quality during flexographic water-based ink printing of coated papers. By changing the key process parameters during flexographic water-based ink printing of coated papers and combined with statistical analysis methods, their effects on the printing effect were studied. The screen density of anilox roll had very important effect on the quality indexes of the printed coated papers, such as density, color difference, printing gloss, color brightness and the abrasion resistance of ink layer. However, the pressure of anilox roller, printing pressure and printing speed, to some extent, had little effects on the above-mentioned quality indexes. Correct selection of screen density of anilox roller is critical to obtain printed coated papers with high printing quality during flexographic water-based ink printing of coated papers.