Appendiceal anomalies are extremely rare malformations that are usually found in adult population as an incidental finding during laparotomy due to another reason. When appendiceal duplications are detected in childhood, almost all the patients have serious associated intestinal, genito-urinary or vertebral malformations. Presented herein are a case of a huge (15 x 13 cm mass) appendiceal duplication in a child causing acute abdomen without an accompanying pathology, its differentiation from appendiceal and caecal diverticulum, and classification of appendiceal duplications with the review of literature.