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

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 Faber	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	Radoslaw Kawecki	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 Tarczynski	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

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

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

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