Cycloteuthis is a genus of squid in the family Cycloteuthidae.

It is distinguished from the genus Discoteuthis by the presence of a tail on the mantle.

The species C. akimushkini is currently considered a junior synonym of C. sirventi, however this is inconclusive and the World Register of Marine Species has C. akimushkini as a valid species.

[1] The genus contains bioluminescent species.

[2] This squid-related article is a stub.