Background: Meconium obstruction (MO) of prematurity can result in increased morbidity or mortality and prolonged hospitalization if not diagnosed and treated appropriately. Objectives: The aims of our study were to identify the incidence and risk factors associated with MO and to review the treatment outcomes. Methods: A retrospective analysis was undertaken of 101 extremely low birth weight infants (ELBWIs) who were born between January 1, 2007, and April 1, 2009, at Seoul National University Hospital. Prenatal and neonatal factors were compared between the MO and control groups. The treatment outcomes were also reviewed. Results: Twenty-two (22%) patients were diagnosed as having MO. Eighteen of these patients (82%) had prenatal risk factors for MO. Respiratory distress syndrome was more prevalent in the MO group than in the control group (p = 0.001). Overall, 17 of the 22 patients (77%) were relieved with medical treatment and the rest underwent ileostomy. The times to full enteral feeding did not differ between the medically treated group and the control group. However, the surgically treated group required more time to achieve full enteral feeding, and some patients had persistent gastrointestinal problems. Conclusion: MO is not a rare condition in ELBWIs, and the majority of ELBWIs have prenatal risk factors. Medical management was effective, and medically manageable cases had good prognoses for subsequent feeding, whereas some surgically managed cases had persistent gastrointestinal problems.