List of fictional alien species: N

Name	Source	Type
Naalu	Twilight Imperium	serpentine telepaths
Naglon	Doctor Who	Humanoid
Nairnama	Independence War, aka I-War
Namekian	Dragon Ball	Humanoid, green skinned beings from planet Namek, they are a powerful race, able to stretch their limbs far distances, manipulate a life energy called ki, regenerate, and have highly enhanced hearing. While all members have masculine appearances, they reproduce asexually, spitting out eggs. Namekians can also choose to either split into two different beings or merge their consciouses and bodies into single beings.
Naram	Renegade Legion	Humanoid
Narn	Babylon 5	Humanoid
Nebulon	Homestar Runner	A bipedal green alien. Whenever he appears, he is told to leave, as "no one likes his style".
Nhar-Gh'Ok	Invader Zim	Humanoid. Resembling babies.
Na'vi	Avatar	Blue humanoid
Nausicaans	Star Trek	Featured on Star Trek
Neadlehead	Win, Lose and Kaboom
Nosedeenian	Ben 10	Also known as Megawhatt. They are small aliens resembling batteries from the Nosedeen Quasar and have electrokinetic powers, including possessing machinery, turning into electricity, and can replicate if sliced in half. While their actions result in destruction, it is not deliberate: they are more akin to innocent pranksters without self-restraint.
Nebari	Farscape	Humanoid
Nebular	Calvin and Hobbes
Necris	Unreal tournament
Necrofriggian	Ben 10	Blue moth-like beings from planet Kylmyys, they possess the ability to phase through matter, and can freeze enemies in different ways, including unleashing freezing winds from their mouth or coating objects in ice via touch. They reproduce asexually every 80 years, laying eggs in nests made of digested metal, which the babies eat when they hatch before moving onto solar plasma.
Necrons	Warhammer 40,000
	Mork and Mindy	Humanoid
Nemet	C. J. Cherryh's Alliance-Union universe
Nephilim	Wing Commander: Prophecy
Neptunians	Futurama	Humanoid, with purple skin, four arms and an upturned nose.
	Futurama	Humanoid, completely grey.
New Gods	The Fourth World in DC Comics
New Orions	Master of Orion III
Nibblonians	Futurama	Small, black and beige creatures with one nostril, small fangs and three eyes, one on a stalk.
	Warhammer 40,000
Niea	Niea 7
Nietzscheans	Andromeda
Nihilanth	Half-Life
Nimbuloids	Ascendancy
	Advent Rising
Nitros Oxide	Crash Bandicoot series
Nodulians	Tracker
Nomads	Freelancer
Nomes	Terry Pratchett's The Bromeliad
Nommo	Master of Orion
N'Orr	Twilight Imperium	water-efficient warrior insectoids
Novus	Universe at War
Nox	Stargate SG-1	Humanoid
Nyronds	passim in the works of ; occasionally in those of his "brother"