Numerous developmental anomalies with respect to crown and root are commonly seen in permanent dentition and while rarely in the primary dentition. Radix entomolaris (RE), an extra root seen on the distolingual aspect of mandibular molars, is one such aberration found. The presence of extra root in primary mandibular first molars is of extreme rarity and such two reports its significance had been discussed. Two children of 5- and 7 years old reported to the pediatric and preventive dentistry department with a chief complaint of pain in the right and left mandibular back teeth region, respectively. A diagnosis of chronic irreversible pulpitis was made in both cases with the accidental appraisal of RE in both the primary first molars on intraoral periapical radiographs. Standard pulpectomy was performed in both cases. Pediatric dentists as well as clinicians should update regarding the abnormal morphologies of primary molars and its diagnostic including treatment strategies.