The 2008 AFC Champions League knockout stage was played from 17 September to 12 November 2008. A total of eight teams competed in the knockout stage to decide the champions of the 2008 AFC Champions League.

The winners of each of the seven groups in the group stage qualified for the knockout stage. West Asia Zone had four teams qualified, East Asia Zone had three plus the title holders.

	Quarter-finals							Semi-finals							Final
	1	Al-Karamah	1	0	1
	8	Gamba Osaka	2	2	4
									Gamba Osaka	1	3	4
									Urawa Red Diamonds	1	1	2
	4	Al Qadisiya	3	0	3
	5	Urawa Red Diamonds ( 2007 Champion)	2	2	4
																Gamba Osaka	3	2	5
																Adelaide United	0	0	0
	3	Kashima Antlers	1	0	1
	6	Adelaide United	1	1	2
									Adelaide United	3	0	3
									Bunyodkor	0	1	1
	2	Saipa	2	1	3
	7	Bunyodkor	2	5	7

The first leg matches were played on 17 September, and the second leg matches were played on 24 September 2008.

Team 1	Agg.Tooltip Aggregate score	Team 2	1st leg	2nd leg
Al-Karamah	1–4	Gamba Osaka	1–2	0–2
Al Qadisiya	3–4	Urawa Red Diamonds	3–2	0–2
Saipa	3–7	Bunyodkor	2–2	1–5
Kashima Antlers	1–2	Adelaide United	1–1	0–1

17 September 2008

19:00 UTC+9

Kashima Antlers	1–1	Adelaide United
Cornthwaite 45+2' ( o.g.)	Report	Dodd 37'

Kashima Soccer Stadium, Kashima

Attendance: 7,004

Referee: Lee Gi-Young ( South Korea)

17 September 2008

21:15 UTC+3:30

Saipa	2–2	Bunyodkor
Razzaghi-Rad 19' Rahmati 40'	Report	Villanueva 12' Rivaldo 20'

Azadi Stadium, Tehran

Attendance: 40,000

Referee: Saad Kameel Al Fadhli ( Kuwait)

17 September 2008

22:00 UTC+2

Al-Karamah	1–2	Gamba Osaka
Abduldaim 7'	Report	Yamaguchi 70' Yamazaki 77'

Khaled bin Walid Stadium, Homs

Attendance: 17,000

Referee: Matthew Breeze ( Australia)

17 September 2008

22:00 UTC+3

Al Qadisiya	3–2	Urawa Red Diamonds
Al Ebrahim 18' Ben Achour 57' Al-Mutairi 84' ( pen.)	Report	Edmilson 33', 90'

Mohammed Al-Hamad Stadium, Kuwait City

Attendance: 12,000

Referee: Masoud Moradi ( Iran)

24 September 2008

16:00 UTC+5

Bunyodkor	5–1	Saipa
Villanueva 9', 19' ( pen.), 52' Rivaldo 45' ( pen.) Luizão 68'	Report	Mirghorbani 47'

MHSK Stadium, Tashkent

Attendance: 15,000

Referee: Muhsen Basma ( Syria)

Bunyodkor won 7–3 on aggregate.

24 September 2008

19:00 UTC+9

Gamba Osaka	2–0	Al-Karamah
Yamazaki 83' Roni 85'	Report

Osaka Expo '70 Stadium, Osaka

Attendance: 9,656

Referee: Sun Baojie ( China)

Gamba Osaka won 4–1 on aggregate.

24 September 2008

19:30 UTC+9

Urawa Red Diamonds	2–0	Al Qadisiya
Soma 31' Tulio 54'	Report

Saitama Stadium, Saitama

Attendance: 41,790

Referee: Benjamin Williams ( Australia)

Urawa Red Diamonds won 4–3 on aggregate.

24 September 2008

19:30 UTC+10:30

Adelaide United	1–0	Kashima Antlers
Cornthwaite 72'	Report

Hindmarsh Stadium, Adelaide

Attendance: 16,965

Referee: Saad Kameel Al Fadhli ( Kuwait)

Adelaide United won 2–1 on aggregate.

The first leg matches were played on 8 October, and the second leg matches were played on 22 October 2008.

Team 1	Agg.Tooltip Aggregate score	Team 2	1st leg	2nd leg
Gamba Osaka	4–2	Urawa Red Diamonds	1–1	3–1
Adelaide United	3–1	Bunyodkor	3–0	0–1

8 October 2008

19:00 UTC+9

Gamba Osaka	1–1	Urawa Red Diamonds
Endō 81' ( pen)	Report	Hosogai 22'

Osaka Expo '70 Stadium, Osaka

Attendance: 17,166

Referee: Abdullah Al Hilali ( Oman)

8 October 2008

19:30 UTC+10:30

Adelaide United	3–0	Bunyodkor
Diego 57' Barbiero 76' Cristiano 89' ( pen)	Report

Hindmarsh Stadium, Adelaide

Attendance: 16,998

Referee: Sun Baojie ( China)

22 October 2008

17:30 UTC+5

Bunyodkor	1–0	Adelaide United
Soliev 78'	Report

MHSK Stadium, Tashkent

Attendance: 17,000

Referee: Ali Hamad Al-Badwawi ( United Arab Emirates)

Adelaide United won 3–1 on aggregate.

22 October 2008

19:30 UTC+9

Urawa Red Diamonds	1–3	Gamba Osaka
Takahara 36'	Report	Yamaguchi 51' Myojin 72' Endō 77'

Saitama Stadium, Saitama

Attendance: 53,287

Referee: Muhsen Basma ( Syria)

Gamba Osaka won 4–2 on aggregate.

The first and second legs of the final were scheduled to be played on 5 November and 12 November 2008, respectively.

Team 1	Agg.Tooltip Aggregate score	Team 2	1st leg	2nd leg
Gamba Osaka	5–0	Adelaide United	3–0	2–0

5 November 2008

19:00 UTC+9

Gamba Osaka	3–0	Adelaide United
Lucas 37' Endo 43' Yasuda 68'	Report

Osaka Expo '70 Stadium, Osaka

Attendance: 20,639

Referee: Malik Abdul Bashir ( Singapore)

12 November 2008

19.30 UTC+10:30

Adelaide United	0–2	Gamba Osaka
		Lucas 4', 15'

Hindmarsh Stadium, Adelaide

Attendance: 17,000

Referee: Subkhiddin Mohd Salleh ( Malaysia)

Gamba Osaka won 5–0 on aggregate.

• Match times were sorted chronologically by local time. The UTC figure given is for the time zone of the place in which the match was held (accounting for Daylight saving time in the areas in which it was in effect).

• AFC Champions League (Knockout Stage Schedule)