A newborn with a patent omphalomesenteric duct is described in this report. This anomaly is a very rare one. Regression of the omphalomesenteric duct occurs as a normal embryonic event in the intrauterine life between the fifth and ninth week of gestation; however, in this case regression occurred spontaneously in the neonatal period and resulted in a Meckel's diverticulum with no connection with the umbilicus. This is the first case to be reported.