This study aims to investigate the effect of background color on the chromatic value of four all-ceramic system core materials at clinically appropriate thicknesses. Disc specimens with 15 mm in diameter and thicknesses ranging from 0.5±0.01mm In-Ceram zirconia core, Cercon base zirconia core, and Cercon base color zirconia core) to 0.8±0.01mm (Empress II) were fabricated. A colorimeter (CIE- 1976-Lab) measured the chromatic value of all samples placed on a high-noble metal-ceramic alloy and a visible light-cured dental composite resin (A2 color) background, after which the color difference was calculated. The color difference of Empress II samples was more than 1.5 among different background color groups, while that of Zirconia was less than 1.5. The influence of background color on the Empress II dentin was visible, such that it could be used on a tooth color post. Meanwhile, the influence of background color was invisible for the three kinds of Zirconia core materia1s, such that the materials developed excellent color-masking abilities and could be adapted for use on any color background.