Swimming at the 2011 World Aquatics Championships – Men's 100 metre backstroke

Prior to the competition, the existing world and championship records were as follows.

	Name	Nation	Time	Location	Date
World record	Aaron Peirsol	United States	51.94	Indianapolis	July 8, 2009
Championship record	Aaron Peirsol	United States	52.19	Rome	August 2, 2009

Heats

50 swimmer participated in 7 heats.^[1]

Rank	Heat	Lane	Name	Nationality	Time	Notes
1	7	4	Camille Lacourt	France	53.30	Q
2	6	5	Jérémy Stravius	France	53.34	Q
3	7	5	David Plummer	United States	53.68	Q
4	6	4	Liam Tancock	Great Britain	53.84	Q
5	6	6	Stanislav Donets	Russia	53.85	Q
6	5	6	Ben Treffers	Australia	53.89	Q
7	7	8	Gareth Kean	New Zealand	53.89	Q
8	5	4	Ryosuke Irie	Japan	53.99	Q
9	7	3	Hayden Stoeckel	Australia	54.05	Q
10	5	3	Nick Thoman	United States	54.13	Q
11	7	6	Aschwin Wildeboer	Spain	54.14	Q
12	5	5	Helge Meeuw	Germany	54.15	Q
13	7	7	Aristeidis Grigoriadis	Greece	54.26	Q
14	5	2	Nick Driebergen	Netherlands	54.30	Q
15	6	3	Junya Koga	Japan	54.32	Q
16	4	1	Guy Barnea	Israel	54.43	swimoff
16	6	1	Sun Xiaolei	China	54.43	swimoff
18	4	5	Thiago Pereira	Brazil	54.47
19	6	7	Mirco di Tora	Italy	54.47
20	6	2	Cheng Feiyi	China	54.60
21	7	2	Vitaly Borisov	Russia	54.66
22	4	7	Charles Francis	Canada	54.68
23	7	1	Daniel Bell	New Zealand	54.75
24	2	4	Omar Pinzón	Colombia	54.88	NR
25	5	8	Jonatan Kopelev	Israel	54.90
26	5	1	Chris Walker-Hebborn	Great Britain	54.91
27	4	4	Guilherme Guido	Brazil	54.93
28	4	6	Radosław Kawęcki	Poland	55.01
29	5	7	Bastiaan Lijesen	Netherlands	55.09
30	4	2	Charl Crous	South Africa	55.14
31	3	5	Gerhard Zandberg	South Africa	55.21
32	4	8	Tobias Oriwol	Canada	55.27
33	4	3	Marcin Tarczyński	Poland	55.28
34	3	3	Péter Bernek	Hungary	55.32
35	6	8	Park Seon-Kwan	South Korea	55.39
36	3	1	Bradley Ally	Barbados	55.88	NR
37	3	6	Federico Grabich	Argentina	55.93
38	3	4	Simon Sjödin	Sweden	56.06
39	3	8	Matas Andriekus	Lithuania	56.10
40	3	7	Flori Lang	Switzerland	56.40
41	3	2	Abdullah Al-Tuwaini	Kuwait	56.94
42	2	3	Jean-François Schneiders	Luxembourg	57.03	NR
43	2	7	Heshan Unamboowe	Sri Lanka	57.95
44	2	5	Alex Hernandez Medina	Cuba	58.15
45	2	6	Charles William Walker	Philippines	58.82
46	1	4	Zane Jordan	Zambia	59.33
47	1	5	Antonio Tong	Macau	1:00.34
48	2	1	Awse Ma'aya	Jordan	1:00.64
49	2	2	Boris Kirillov	Azerbaijan	1:01.03
50	1	3	Andrey Molchanov	Turkmenistan	1:05.39

Swimoff

As two swimmers had the same time in the heats at place 16 they had to participate in a swimoff to determine the last semifinal swimmer, it was held at 11:36.^[2]

Rank	Lane	Name	Nationality	Time	Notes
1	5	Sun Xiaolei	China	54.20	Q
2	4	Guy Barnea	Israel	55.12

Semifinals

The semifinals were held at 18:10.^[3]

Semifinal 1

Rank	Lane	Name	Nationality	Time	Notes
1	4	Jérémy Stravius	France	52.76	Q
2	6	Ryosuke Irie	Japan	53.05	Q
3	7	Helge Meeuw	Germany	53.34	Q
4	2	Nick Thoman	United States	53.49	Q
5	5	Liam Tancock	Great Britain	53.60	Q
6	3	Ben Treffers	Australia	53.87
7	1	Nick Driebergen	Netherlands	53.98
8	8	Sun Xiaolei	China	54.21

Semifinal 2

Rank	Lane	Name	Nationality	Time	Notes
1	4	Camille Lacourt	France	53.09	Q
2	5	David Plummer	United States	53.30	Q
3	6	Gareth Kean	New Zealand	53.69	Q
4	2	Hayden Stoeckel	Australia	53.70
5	7	Aschwin Wildeboer	Spain	54.03
6	3	Stanislav Donets	Russia	54.10
7	8	Junya Koga	Japan	54.16
8	1	Aristeidis Grigoriadis	Greece	54.22

Final

The final was held at 19:06.^[4]

Rank	Lane	Name	Nationality	Time	Notes
	3	Camille Lacourt	France	52.76
	4	Jérémy Stravius	France	52.76
	5	Ryosuke Irie	Japan	52.98
4	7	Nick Thoman	United States	53.01
5	6	David Plummer	United States	53.04
6	1	Liam Tancock	Great Britain	53.25
7	2	Helge Meeuw	Germany	53.28
8	8	Gareth Kean	New Zealand	53.50	NR

• 2011 World Aquatics Championships: Men's 100 metre backstroke start list^{[permanent dead link]}, from OmegaTiming.com; retrieved 2011-07-23.