Impacted canines are not uncommon, but movement of impacted canine crossing the midline (transmigration) is a rare phenomenon. The study discusses the case report of a transmigrated mandibular canine associated with a dentigerous cyst in a 17-yearold female patient. Mandibular canines are cornerstones of dental arch and their importance is manifested by stability of dental arch, maintenance of normal facial expression, and masticatory efficiency. Early detection of this condition by the use of radiographs, especially panoramic radiographs, and preserving the canine by orthodontic intervention or surgical transplantation are needed.