Introduction: Meconium peritonitis is a rare disease which can be potentially fatal. Case Report: We present the history of a full-term male infant born at 2945 g via lower segment cesarean section (LSCS). There was an antenatal diagnosis of an intra-abdominal cyst. At 27+6 weeks gestation, the ultrasound scan noted a thick-walled cystic mass superior to the bladder. Postnatally, an X-ray showed a paucity of gas in the right lower quadrant and an ultrasound scan confirmed a large central avascular cystic lesion, with posterior sediments noted. Laparotomy revealed extensive adhesions surrounding a meconium filled cyst. This was excised and a primary anastomosis performed. However, he failed to progress with feeds, having intermittent abdominal distension, and after a contrast study on day 18 post op which showed failure of contrast to pass the dilated proximal jejunum, he was taken back to the operating room and was found to have significant adhesions. Adhesiolysis was done and the anastomosis was patent and well healed. However, these episodes of abdominal distension continued, and he never progressed with feeds. On day 39 of life, there was severe metabolic acidosis refractory to resuscitation, leading to cardiac arrest. Conclusion: There can be subtle presentations of meconium peritonitis in the newborn and it should be considered in any neonate with an intra-abdominal cyst.