to analyze root canals morphology and existence of extra canals in maxillary molars in Saudi subpopulation. Freshly extracted maxillary first molars [n=100] were included in this study. All teeth were examined for morphology of roots, root canals and apical foramen by Cone Beam Computed Tomography [CBCT] . The root canals configuration was classified using Vertucci's classification. The majority of maxillary first molars [94%] were having three distinctly separated roots and 6% had four roots. Palatal and distobuccal roots were observed to contain one root canal [100%] and Vertucci's type I configuration. The mesiobuccal root had one [29.4%; type I] or two canals [70.6%; type II, III or IV] . The occurrence of second canal in the mesiobuccal root of upper first molar is very much likely [>70%] . The mesiobuccal roots are more likely to have Vertucci's type I or II configuration [>76%] . The palatal and distobuccal roots always have a Vertucci's type I canal configuration