Earthforce is the military, scientific, and exploratory arm of the Earth Alliance.
- See: Main Article Earthforce Ranks for details on Earthforce rank structure.
Earthforce is composed of three separate branches: Fleet, Marines, and Security. Flag officers from all three divisions comprise a Joint Chiefs of Staff who report directly to the President of the Earth Alliance. Personnel may transfer between divisions - Richard Franklin served in the Fleet early in his career, but by the time we actually see him (in "GROPOS"), he is a General in the Marines.
Earthforce Space Corps
The Earthforce Space Corps, or simply 'Fleet' is the backbone of Earthforce, encompassing all of the space borne military assets of the Earth Alliance. Fleet officers wear a standard blue uniform with the Earth Alliance Emblem on the left breast over an appropriate stat bar, with a unit patch or flight wings on the right upper shoulder and a divisional badge on the left. Pilot flight uniforms feature the owner's name over the left breast, the divisional patch on the right breast, a unit (wing) patch on the right upper shoulder and the squadron patch on the left upper shoulder. Flight-suits have a large rectangular patch over the left breast that display the pilot's name, rank and flight qualification. The duty uniform of a fleet NCO is the same as that of the officers sans the stat bar and the vertical leather strip on the tunic and in place of the divisional patch on the upper left arm is instead a unit or ship patch.
All Earthforce military vessels have the registry prefix EAS, which stands for Earth Alliance Ship.
Earthforce Medical Corps
Though technically separate, the Earthforce Medical Corps, or Medcorps is effectively attached to both the Space & Marine Corps and responsible for the medical requirements of all Earthforce personnel. All senior officers must be qualified medical doctors registered through the E.M.A. and as such rarely come from a military background.
Earthforce Security Corps
Earthforce Security is the branch of Earthforce that employs and trains appropriately qualified peace officers from the local population to act as a security force on all Earthforce ground and space stations (starship security being handled by the Marine Corps.) Like any police force, Earthforce Security personnel are required to enforce the civil laws of the Earth Alliance and adhere to the rule of due process. Various people in the service have different clearance levels. Garibaldi, for example, holds clearance "ultraviolet alpha" which contextually seems to be a high clearance level.
The standard security uniform is light grey, with personnel ranking Sergeant and below the tunic is sans the normal leather strip and displays the Earthforce security badge over the left breast with rank insignia on the epaulettes and the unit patch on the left shoulder. NCO's wear a grey Earthforce uniform with a division patch of the left upper arm and a stat bar beneath the EA emblem.
Earthforce Marine Corps
The Earthforce Marine Corps are the ground forces of the Earth Alliance. Marine officers wear a brown Earthforce uniform while NCOs and enlisted wear olive fatigues that display the owner's name over the left breast, rank insignia on the right upper sleeve and the emblem of the Marine Corps printed over the left side of the abdomen.
Enlistment in Earthforce is open to all humans of the Earth Alliance deemed both fit and qualified to serve without prejudice to creed, gender or faith. However telepaths were originally prohibited from service in Earthforce, though following the Telepath War and the dismantling of the Psi Corps new rules were instituted to allow the integration of telepaths and normals.
Normally, Earthforce is a strictly professional force with a volunteer-only recruiting policy. However, during the Earth-Minbari War, a planetary draft was implemented on all Earth Alliance citizens not deemed exempt, to compensate for losses suffered during the war.
- Earthforce Academy: Earthforce's primary facility for officer training.
- Earthforce Postal Service: The Earth Alliance's military postal system, allowing serving EF personnel to receive packages from home, no matter where they might be posted.
- Earthforce Research & Development Division: Division responsible for the development of Earthforce equipment and technology.
- Earthforce Internal Affairs Division: EIAs, or "Eyes" as it's commonly called, is the branch of Earthforce that oversees the conduct of members of Earthforce. EIA personnel may be drawn from any of the three EarthForce branches. EIA tests the loyalty of Earthforce members if they are suspected of acting against Earth's interests. In 2258, Colonel Ari Ben Zayn led an investigation regarding the loyalty of the Babylon 5 staff, specifically Commander Jeffrey Sinclair. He was assisted by Harriman Gray, a Psi Corps telepath assigned to Ben Zayn under the authority of Alfred Bester.
- Earthforce Intelligence Gathering Division: Advance reconnaissance division. Marcus Cole was once assigned to this division during the Earth-Minbari War. 
- Earthforce Special Intelligence Division: An investigation and research organization within Earthforce. Usually responsible for investigating possible new threats to Earth and is the only division of Earthforce to be under the direct authority of the President of the Earth Alliance. In 2260 ESI Agent David Endawi was sent to Babylon 5 to determine what the alien Ambassadors knew about a new race who's ship was recently shown on ISN, destroying an Earth Alliance Starfury.
- Earthforce Bio-weapons Division: Specialist division of Earthforce concerned with research and development of biological weapons systems that has been known to have close ties with IPX and "Earthforce New Technologies Division".
- Earthforce New Technologies Division: Earthforce New Technologies is primarily concerned with the investigation and discovery of advanced technology discovered on alien worlds. Most often from ancient and dead civilisations. Has close ties with IPX and Earthforce Bio-weapons Division. During the Icarus mission, Earthforce New Technologies Division put Doctor Chang under strict orders to keep the true mission objective top secret and assigned Doctor Morden to his team.
Earthforce sends out daily status reports to keep different entities informed. In 2258, Susan Ivanova notes that there is commonly mention of Mars, though if a military exercise is going on, mention will be omitted and communicated through other channels.
Citations and Medals
Earthforce Medal of Honour
The Earth Alliance's highest honour. Following Captain Sheridan's successful campaign to topple President Clark, President Susanna Luchenko told Sheridan that half of Earthforce wanted to give him the Medal of Honor, while the other half wanted him taken out and shot. She jokingly suggested doing both in that order might be a fair compromise. 
- Known Recipients
The Silver Star was one of the highest Earth Alliance military decorations awarded to members of Earthforce. The medal is awarded for bravery and valour in the face of the enemy.
- Known Recipients
- Stephen Walters - (Battle of Douala)
- David McIntyre - (During the Earth-Minbari War) 
- John Sheridan - (Battle with the Black Star, Earth-Minbari War) 
- Jeffrey Sinclair - (During the Earth-Minbari War) 
Battle of the Line Medal
A rare citation awarded only to the two hundred or so survivors of the Battle of the Line. The medal features a representation of Earth surrounded by twelve stars and the words: -
"THE LINE • IN GRATITUDE & MEMORY".
- Known Recipients
- Deathwalker (episode)
- "Sorry. Communications are out except for authorized personnel." "Let me get this straight. I'm an Earthforce security officer, clearance ultraviolet alpha, and I'm not considered authorized personnel?" -A Voice in the Wilderness, Part I
- A Late Delivery from Avalon
- GROPOS (episode)
- Eyes (episode)
- To Dream in the City of Sorrows
- Matters of Honor
- Z'ha'dum (episode)
- The Shadow Within
- A Voice in the Wilderness, Part I
- Rising Star
- Patterns of the Soul
- Dark Genesis - The Birth of the Psi Corps
- A Late Delivery from Avalon
- Voices of Authority
- The War Prayer
- The Gathering