The first stage of the alien's life cycle consists of an egg. The eggs are complex organisms in and of themselves. They are responsible for maintaining life support for the larva for an indefinite amount of time, and must recognize a potential host and distinguish it from valid members of the nest. Eggs are initially created inside a queen alien and enter the world (after being queued in her extended abdomen) via slimy tube to stand on their own. The egg itself is a leathery object approximately 2.5 feet tall.

The egg can survive for an undetermined length of time in various environments. The egg appears translucent, is flammable, and unarmored. The egg detects when a host is proximal by sound and/or movement. As this happens, some sort of liquid seems to drip upward, and small bumps appear as the egg comes to live, awakened by the chance to continue it's lifecycle. The petals at the top of the egg open, preparing for the next stage as the face-hugger.