Background and objectives: Cleaning and shaping principles of root canal must aim to respect the continuously tapering funnel from the root apex to the coronal access cavity, follow the original canal shape and maintain the apical foramen in its original spatial relationship to the periapical tissues and root surface. This study was conducted to compare centering ability using: XP endo shaper, Edge Evolve and Hyflex CM nickeltitanium instruments in simulated curved canals. Materials and methods: Sixty simulated curved canals of 40°curvature were divided into three groups and prepared to an apical size 30 using single-length technique for XP endo shaper, crown-down technique for Edge Evolve and Hyflex CM instruments. Centering ability was evaluated; the measurements were carried out at five different levels. Pre-and postoperative images of the canals were taken at a standardized position by a digital camera (Nikon D810-36 Megapixels, Japan) with 60mm macro lens. An assessment of the shape of the canal was determined using AutoCAD sofware. The data were analyzed statistically using one way ANOVA, Welch ANOVA, Least significant differences (LSD) and Games-Howell post hoc test. Results: the results of this study demonstrated that the Edge Evolve instruments showed a significantly better centering ability than both XP endo shaper and Hyflex CM at four levels of measurements except at last level (HO) which XP endo shaper scores the best centering ability. The Hyflex CM and XP endo shaper instruments scores similar results and were mostly close to each other after Edge Evolve instruments regarding canal centering ratio. Conclusions: The study demonstrated that Edge Evolve file maintained the original curvature significantly better than Hyflex CM and XP endo shaper files.