Objective The objective of this study was to evaluate the color change of discolored tooth after restored with IPS-EMPRESS Ⅱ ceramics. Methods 30 anterior tetracycline teeth were veneered and 30 anterior discolored teeth after root canal treatment were restored with full crowns. The ShadeEye-NCC color system was used to analyze the change in L, a and b. Then the chromatism[（ΔEab=（ΔL2+Δa2+Δb2）1/2）] as well as the value of Lab （ Lab=L）, Cab[（Cab=（a2+b2）1/2）] and Hab[（Hab=arctan（b/a）] were calculated. Results After veneered and crowned the teeth’s color had obviously changed. Additionally, there were some color changes of 60 teeth between before and after bonding. The average chromatism of the veneered teeth reached 2.37, and the Lab, Cab and Hab had statistical differences（P
