The Dominators' mothership is a spaceship used a base of operations by the Dominators.
The Dominators came to Earth in the mothership, sending four drop ships to Earth to gather intel on humans. After kidnapping Sara Lance, John Diggle, Thea Queen, Ray Palmer and Oliver Queen, the Dominators placed them into an induced dream world. They eventually escaped, fending off the Dominators and stealing an escape pod. The Dominators followed them towards Earth in the mothership. They flew back into space after their plan to detonate the metabomb had failed.