The present in-vitro study was undertaken to know root canals and their configuration (type, curvature, number of apical foramen etc) in maxillary second permanent molar. Separately, fifty teeth by radiographic method and by decalcification method were studied. Radiologically in mesiobuccal root, two root canals were found in 78% and 20% of the specimens in mesiodistal and buccolingual direction respectively. In the distobuccal root, 2 root canals were seen in 4% and 6% of the specimen in mesiodistal and buccolingual direction respectively. Two root canals also varied in both radiological as well as decalcification methods. It is concluded from the present study that mesiobuccal roots of maxillary second molar exhibited anatomical variations and aberrant findings in the root canals. More care should always be exercised to locate the extra canal in these roots.