Development of human adrenal medulla has always been a topic of quandary because of insufficient literature. Most of the studies on adrenal medulla pertain to various species of animals but human fetuses. This research work emphasizes on the developmental chronology of events by studying 36 human fetal adrenal medullas. This study confirms that neural crest derived sympathoblasts migrate through the cortex into the medulla at 12 weeks as opposed to the prevalent view of 8 weeks in animal studies. Cortical and medullary differentiation begins at 12 weeks of gestation and is complete by 16 weeks. Medullary sinusoids appear at 16 weeks. Adrenaline and noradrenaline secreting cells are separate entities and they differentiate from the chromaffin cells at 22 weeks. Moreover ganglionic cells are seen in the medulla for the first occasion at 22 weeks. It is imperative to understand the human medullary differentiation in order to shed light on emerging diseases due to developmental anomalies of adrenal medulla.