Orbeez is a small toy made of a highly expandable, which has recently become popular in Korea. These beads can expand to 100 times or more its volume when in contact with water and can also be expected to grow in size when ingested. We encountered two pediatric patients who swallowed Orbeez and developed small bowel obstruction. In the first case, surgery was performed without knowing that the small bowel obstruction was caused by Orbeez. In the second case, based on the experience gained from the first case, a detailed history was taken, including the possibility of Orbeez ingestion to determine the cause of the small bowel obstruction. We diagnosed the cause of the small bowel obstruction early, followed by rapid treatment. We recommend that emergency department physicians must consider Orbeez as the cause of small bowel obstruction in children.