Abstract: Meconium peritonitis is a sterile chemical peritonitis resulting from intestinal perforation in-utero. We present a preterm male neonate weighing 1820 g in whom foetal meconium peritonitis was diagnosed by antenatal utrasonogram. Examination of the newborn in the immediate postnatal period revealed a firm lump of size 5 × 3 cm in the right lumbar and umbilical area. Rest of the abdomen was normal without any clinical evidence of intestinal obstruction. X-ray of abdomen done at 3 hours of life showed a cystic mass with calcified margin. Ultrasonography of abdomen ruled out any definite cause of intestinal obstruction and perforation. He was kept on conservative management. At 11 hours of life the neonate passed a small sticky white mucus plug per rectum followed by black colored meconium of normal consistency 2 hours later. The bowel habit remained regular thereafter. Screening for intrauterine infections and cystic fibrosis was negative. He is under regular follow-up and is now 6 months old with normal bowel habit. A lump of size 2 × 2 cm is still palpable and a small calcified mass is persistent in x-ray. Role of an intestinal mucus plug as the potential factor for intestinal obstruction and subsequent perforation has been highlighted in the present case.