- Colonel Jonathan "Jack" O'Neill, USAF (played by Richard Dean Anderson)
- Rank: Colonel SN 66-789-7876-324
- Status: Active Duty Joint Forces Unit SGC
- Current Assignment: Team Leader SG-1
- Background Information: Military representative and C.O. of SG-1 Team.
- Standing Orders: C.O. SG-1 Team. Defend earth from possible hostile invasion. Explore new worlds and return new technologies military or otherwise for study and further development.
- Previous Service/Special training: Covert Operations/Infiltration, Special Weapons and Tactics, Demolition, Chemical Weapons, Field Expediance Specialist
- Personal Status: Marital Status: Single, Children: (1) Deceased
- Recalled to active duty
