A Ngultor mothership was a very large type of starship used by the Ngultor race. They were many times larger than a Constitution-class starship, and like all Ngultor technology, entirely organic.

In 2254, in a freak warp accident, a Ngultor mothership ended up in a region of space in or near Federation territory. The Ngultor sent out their ship's support craft to gather biological matter to repair their damaged mothership. These harvests left behind a trail of starships devoid of life.

Starfleet sent the USS Enterprise to investigate the situation and one of the mothership's support craft captured the starship to take back to the mothership to harvest the large crew. Whilst in transit Captain Christopher Pike learnt of the Ngultor’s plans to return to the region to harvest the flesh of the many species they had encountered. Not willing to let the Federation and its neighbours be consumed, Pike destroyed the mothership rather than let it return to Ngultor space. (EV comic: "Flesh of My Flesh")