The name Jefferies could refer to the following;
- W.M. Jefferies - an engineer and captain in the United Earth Starfleet in the mid 22nd century.
- Benjamin McDonald-Jefferies - the son of George William Jefferies and a civilian engineer.
- Frederick William Jefferies - the son of Benjamin McDonald-Jefferies and a Starfleet engineer who was most notable for designing the Jefferies tubes.
- William Jefferies - 23rd century admiral.
- Matt Jefferies - the art director and production designer of The Original Series.
- USS Jefferies (Galaxy class) - a Galaxy-class starship in service in the 24th century.
- Jefferies (shuttlecraft), a shuttlecraft attached to the USS Enterprise-E
- Unnamed Federation shuttlecraft classes#Jefferies' shuttlecraft - a type of shuttlecraft in use during the 23rd century.
- USS Jefferies (NCC-1750) - a 23rd century shuttlecraft.
- Jefferies tube - part of a network of service tubes found on Federation vessels that enabled rapid access to ships systems.