Все нижеперечисленные треки были написаны музыкантом Келли Бэйли. Некоторые из них являются оригинальными треками из Half-Life, в HL2 они переименованы. Обладатели специального коллекционного издания игры, помимо прочих бонусов, получили CD с оригинальными саундтреками. Этот CD отдельно не продается.

Треки 16, 18 и 42 представлены только на CD. Треки 44 - 51 не включены в состав CD, но есть в игре.

1. "Hazardous Environments" (Valve Theme [Long Version]) - 01:26

2. "CP Violation" - 01:47

3. "The Innsbruck Experiment" - 01:09

4. "Brane Scan" - 01:42

5. "Dark Energy" - 01:34

6. "Requiem for Ravenholm" - 00:35

7. "Pulse Phase" - 01:11

8. "Ravenholm Reprise" - 00:54

9. "Probably Not A Problem" - 01:28

10. "Calabi-Yau Model" - 01:48

11. "Slow Light" - 00:46

12. "Apprehension and Evasion" - 02:19

13. "Hunter Down" - 00:17

14. "Our Resurrected Teleport" - 01:13

15. "Miscount Detected" - 00:50

16. "Headhumper" - 00:10

17. "Triage at Dawn" - 00:47

18. "Combine Harvester" - 01:27

19. "Lab Practicum" - 02:56

20. "Nova Prospekt" - 01:59

21. "Broken Symmetry" - 01:05

22. "LG Orbifold" - 02:54

23. "Kaon" - 01:13

24. "You're Not Supposed to Be Here" - 02:43

25. "Suppression Field" - 00:57

26. "Hard Fought" - 01:17

27. "Particle Ghost" - 01:42

28. "Shadows Fore and Aft" - 01:28

29. "Neutrino Trap" (Hurricane Strings) - 01:37

30. "Zero Point Energy Field" (Cavern Ambiance) - 01:44

31. "Echoes of a Resonance Cascade" (Space Ocean) - 01:40

32. "Black Mesa Inbound" (Vague Voices) - 02:15

33. "Xen Relay" (Threatening Short) - 00:41

34. "Tracking Device" (Credits / Closing Theme) - 01:05

35. "Singularity" (Traveling Through Limbo) - 01:21

36. "Dirac Shore" (Dimensionless Deepness) - 01:28

37. "Escape Array" (Electric Guitar Ambiance) - 01:29

38. "Negative Pressure" (Steam in the Pipes) - 01:59

39. "Tau-9" (Drums and Riffs) - 02:08

40. "Something Secret Steers Us" (Nuclear Mission Jam) - 02:04

41. "Triple Entanglement" (Sirens in the Distance) - 01:34

42. "Biozeminade Fragment" (Alien Shock) - 00:34

43. "Lambda Core" (Diabolical Adrenaline Guitar) - 01:44

44. "Entanglement" - 00:39

45. "Highway 17" - 00:59

46. "A Red Letter Day" - 00:39

47. "Sand Traps" - 00:34

48. "CP Violation (Remix)" - 01:45

49. "Trainstation PT. 1" - 01:30

50. "Trainstation PT. 2" - 01:12

51. "Radio" 00:39