Recently, documentation highlighting the prevalence of over 4 root canals in mandibular 1st molars has emerged. While treating mandibular 1st molars that require endodontic treatment, clinician should be cautious. Furthermore, radiographic evaluation should be viewed as a tool for obtaining clues rather than a definitive reference to anatomy as well as its accompanying anomalies. The non-surgical endodontic therapy of a mandibular 1st molar having six root canals, 3 in each mesial & distal root, is described in this case. Complete restoration of the tooth was achieved with a composite preceded by a PFM crown after non-surgical endodontic therapy. This specific example contributes to the growing body of knowledge about mandibular 1st molars with six root canals, emphasising the importance of uncommon morphological aberrations in these teeth.