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The development of the adrenal cortex is dependent on blood supply, paracrine adrenal factors, hormonal factors, and adrenocortical innervation.

In contrast, the definitive adult cortex arises from cellular hyperplasia associated with decreased apoptosis. After birth, shrinkage of the fetal zone due to increased apoptotic activity occurs. The human fetal adrenal cortex consists of two parts, the fetal and the definitive adult zones. In later stages of embryonic development, the cortex engulfs, and ultimately encapsulates the entire medulla.

At 7 weeks of gestation, sympatho-adrenal cells migrate into the adrenal primordium. This tissue gives rise to the fetal adrenal cortex and to Lyedig cells. An isolated clump of cells appears within the urogenital ridge, known as the adrenal-gonadal primordium. The adrenal gland is composed of two embryologically distinct tissues, the cortex and medulla, arising from the mesoderm and neuroectoderm, respectively.