The aim of this study is to compare the colour stability of Monolithic Zirconia and layered Zirconia after immersion in commercially available mouthwash and food-simulating liquids (FSLs). Material and Methods: 40-disc shaped specimen, 20 discs of each material with diameter of 10 mm and thickness 2 mm were prepared with CAD/CAM techniques following standard set protocols. Two groups, Group NA: Specimens fabricated from monolithic Zirconia (MZ), (UPCERA INDIA CAD ST, SHADE A2) 2. Group NB: Specimens fabricated from monolithic Zirconia veneered/layered with lithium Disilicate (LZ), (UPCERA INDIA CAD ST, SHADE A2 veneered with IPS e.max) were divided into 4 sub-groups; All the samples were immersed in different staining solutions over a 28-day test period. Acolorimetric evaluation according to the CIE L*a*b* system was performed by a trained operator at 28 days of the staining process. Kruskal-Wallis and Mann Whitney U test were applied to assess significant differences among restorative materials. Results: ∆E values for MZ with the immersion of saliva, mouthwash, coffee, cola were 0.4, 2.23, 4.98, 3.72 respectively. Corresponding ∆E values for LZ were 0.34, 0.84, 1.8 and 1.02; MZ has marginally higher values than the clinically acceptable level of 3.5 in coffee and cola. Conclusion: Both monolithic zirconia and layered Zirconia underwent colour changes after immersion in FSLs and commercially available mouthwash.