The Asian hornet is described as a “significant predator” which hunts other insects in the UK.
The nest, the first seen in Sussex since at least 2016 according to government records, comes amid fears surrounding the rising number of Asian hornets in the country.
The Department for the Environment, Farming and Rural Affairs (Defra) confirmed the nest was spotted in Newhaven on August 15. It was later destroyed.
It coincides with a dramatic rise in sightings in Kent, with 17 of the 22 sightings in the UK this year coming in the neighbouring county.
Originally native to Asia, the hornets are predators who eat other insects including honey bees.
They were introduced to France in 2004 and have since been spotted in the UK.
Fears are that nests of Asian hornets could disrupt the insect eco-system in the UK.
Asian hornets are a similar size to hornets and much larger than wasps and honey bees.
They are black with a wide orange segment on the abdomen and have yellow legs.
Asian hornets also have a “very deep buzz” compared with other species of bee and hornet, according to the British Beekeepers Association.
Speaking on the threat to other species, the Royal Society for Protection of Birds (RSPB) said: “The concern around the Asian hornet is that it is a significant predator of bees.
“In France, it has consumed large numbers of bees, including the well-known European honey bee and many lesser-known solitary and colonial bee species.
“Nature conservation organisations, including the RSPB, are concerned about the impacts of Asian hornets on bees, as these pollinating species are an essential component of well-functioning ecosystems.”
Asian hornets are most active between April and November, with a peak in August and September.