# Swimming at the 2003 World Aquatics Championships – Men's 50 metre backstroke

The Men's 50 Backstroke event at the 10th FINA World Aquatics Championships swam July 26–27, 2003 in Barcelona, Spain. Preliminary and Semifinal heats were on July 26, with the Final swum on July 27.
Prior to the start of the event, the existing World (WR) and Championship (CR) records were:
* WR: 24.99 swum by Lenny Krayzelburg (USA) on August 28, 1999 in Sydney, Australia
* CR: 25.31 swum by Thomas Rupprath (Germany) on July 24, 2001 in Fukuoka, Japan

## Results
### Final

| Place | Swimmer | Nation | Time | Notes |
| 1 | Thomas Rupprath | Germany | 24.80 | WR |
| 2 | Matt Welsh | Australia | 25.01 | |
| 3 | Gerhard Zandberg | South Africa | 25.07 | |
| 4 | Steffen Driesen | Germany | 25.14 | |
| 5 | Randall Bal | USA | 25.19 | |
| 6 | Darius Grigalionis | Lithuania | 25.53 | |
| 7 | Josh Watson | Australia | 25.62 | |
| 8 | Aaron Peirsol | USA | 25.75 | |

### Semifinals

| Rank | Heat + Lane | Swimmer | Nation | Time | Notes |
| 1 | S2 L4 | Thomas Rupprath | Germany | 25.07 | q, CR |
| 2 | S1 L4 | Steffen Driesen | Germany | 25.38 | q |
| 2 | S1 L6 | Gerhard Zandberg | South Africa | 25.38 | q |
| 4 | S2 L6 | Aaron Peirsol | USA | 25.47 | q |
| 5 | S1 L1 | Josh Watson | Australia | 25.50 | q |
| 6 | S2 L5 | Randall Bal | USA | 25.51 | q |
| 7 | S1 L5 | Matt Welsh | Australia | 25.52 | q |
| 8 | S1 L3 | Darius Grigalionis | Lithuania | 25.61 | q |
| 9 | S2 L3 | David Ortega | Spain | 25.62 | |
| 10 | S2 L7 | Alex Lim | Malaysia | 25.68 | |
| 11 | S2 L8 | Ouyang Kunpeng | China | 25.74 | |
| 12 | S1 L7 | Tomomi Morita | Japan | 25.79 | |
| 13 | S1 L2 | Ahmed Hussein | Egypt | 25.81 | |
| 14 | S2 L2 | Arkady Vyatchanin | Russia | 25.91 | |
| 15 | S1 L8 | Atsushi Nishikori | Japan | 25.95 | |
| 16 | S2 L1 | Vyacheslav Shyrshov | Ukraine | 25.99 | |

### Preliminaries

| Rank | Heat+Lane | Swimmer | Nation | Time | Notes |
| 1 | H13 L4 | Thomas Rupprath | Germany | 25.19 | q, CR |
| 2 | H13 L5 | Steffen Driesen | Germany | 25.48 | q |
| 3 | H12 L8 | Randall Bal | United States | 25.53 | q |
| 4 | H12 L4 | Matt Welsh | Australia | 25.60 | q |
| 5 | H11 L4 | David Ortega | Spain | 25.71 | q |
| 6 | H13 L3 | Darius Grigalionis | Lithuania | 25.76 | q |
| 6 | H13 L8 | Aaron Peirsol | United States | 25.76 | q |
| 8 | H12 L5 | Gerhard Zandberg | South Africa | 25.80 | q |
| 9 | H12 L2 | Arkady Vyatchanin | Russia | 25.85 | q |
| 10 | H11 L2 | Ahmed Hussein | Egypt | 25.89 | q |
| 11 | H12 L3 | Alex Lim | Malaysia | 25.93 | q |
| 11 | H12 L7 | Tomomi Morita | Japan | 25.93 | q |
| 13 | H10 L8 | Vyacheslav Shyrshov | Ukraine | 25.97 | q |
| 14 | H11 L5 | Josh Watson | Australia | 26.01 | q |
| 15 | H11 L6 | Ouyang Kunpeng | China | 26.08 | q |
| 15 | H13 L6 | Atsushi Nishikori | Japan | 26.08 | q |
| 17 | H10 L4 | Viktor Bodrogi | Hungary | 26.11 | |
| 18 | H13 L7 | Nuno Laurentino | Portugal | 26.13 | |
| 19 | H08 L8 | Örn Arnarson | Iceland | 26.18 | |
| 20 | H10 L7 | Gregor Tait | Great Britain | 26.23 | |
| 21 | H12 L6 | Riley Janes | Canada | 26.24 | |
| 22 | H13 L2 | Péter Horváth | Hungary | 26.25 | |
| 23 | H10 L1 | Markus Rogan | Austria | 26.26 | |
| 23 | H13 L1 | Min Sung | South Korea | 26.26 | |
| 25 | H10 L5 | Blaž Medvešek | Slovenia | 26.29 | |
| 26 | H09 L5 | Jani Sievinen | Finland | 26.30 | |
| 27 | H10 L2 | Pavlo Illichov | Ukraine | 26.34 | |
| 28 | H11 L1 | Ales Volcansek | Croatia | 26.35 | |
| 29 | H12 L1 | Ryan Pini | Papua New Guinea | 26.37 | |
| 30 | H11 L3 | Flori Lang | Switzerland | 26.46 | |
| 31 | H10 L3 | Gordan Kožulj | Croatia | 26.48 | |
| 32 | H08 L5 | Pablo Martin Abal | Argentina | 26.49 | |
| 33 | H09 L1 | Pavel Suškov | Lithuania | 26.61 | |
| 34 | H09 L2 | Jens Petersson | Sweden | 26.64 | |
| 34 | H09 L7 | Yoav Gath | Israel | 26.64 | |
| 36 | H09 L8 | Alexandr Ivlev | Moldova | 26.73 | |
| 37 | H08 L4 | Martin Viilep | Estonia | 26.76 | |
| 38 | H09 L3 | Eric la Fleur | Sweden | 26.83 | |
| 39 | H09 L4 | Paulo Machado | Brazil | 26.86 | |
| 40 | H11 L8 | Cameron Gibson | New Zealand | 26.94 | |
| 41 | H01 L3 | Rui Yu | China | 26.99 | |
| 42 | H11 L7 | Orel Oral | Turkey | 27.07 | |
| 43 | H08 L2 | Rogério Romero | Brazil | 27.49 | |
| 44 | H08 L3 | Oleg Pukhnaty | Uzbekistan | 27.75 | |
| 45 | H07 L4 | Nicholas Bovell | Trinidad and Tobago | 28.10 | |
| 46 | H08 L7 | Mauricio Prudencio | Bolivia | 28.15 | |
| 47 | H06 L2 | Gustavo Vera | Paraguay | 28.31 | |
| 48 | H07 L5 | Albert Subirats | Venezuela | 28.35 | |
| 49 | H06 L4 | Jared Heine | Marshall Islands | 28.38 | |
| 50 | H08 L6 | Ashby Brendan | Zimbabwe | 28.41 | |
| 51 | H07 L8 | Ismael Ortiz | Panama | 28.60 | |
| 52 | H07 L3 | Guillermo Andres Ramirez Lemis | Colombia | 28.72 | |
| 53 | H07 L2 | V. Arun Vellore | India | 28.76 | |
| 54 | H03 L5 | Onan Thom | Guyana | 28.80 | |
| 55 | H08 L1 | Mikhail Alekseyev | Uzbekistan | 28.82 | |
| 56 | H06 L6 | Yau Sun Fai | Hong Kong | 29.01 | |
| 57 | H06 L3 | Asela Pradeep Perera | Sri Lanka | 29.21 | |
| 58 | H06 L7 | Chi Lon Lei | Macau | 29.24 | |
| 59 | H07 L6 | Abed Rahman Kaaki | Lebanon | 29.25 | |
| 60 | H05 L5 | Khaly Ciss | Senegal | 29.26 | |
| 61 | H06 L5 | Roberto Sanso | Costa Rica | 29.33 | |
| 62 | H05 L8 | Ranui Teriipaia | Tahiti | 29.41 | |
| 63 | H05 L4 | Olufolahan Oluwole | Nigeria | 29.43 | |
| 64 | H06 L1 | Rony Bakale | Republic of the Congo | 29.66 | |
| 65 | H06 L8 | Mohammad Nazeri | Iran | 29.74 | |
| 66 | H05 L6 | James B. Walsh | Philippines | 29.80 | |
| 67 | H04 L3 | Davy Bisslik | Aruba | 29.92 | |
| 68 | H04 L7 | Joao Aguiar | Angola | 29.98 | |
| 69 | H05 L3 | Rubel Mohammad Rubel Rana | Bangladesh | 30.01 | |
| 70 | H07 L1 | Omar Abu Faris | Jordan | 30.06 | |
| 71 | H07 L7 | Yury Zaharov | Kyrgyzstan | 30.20 | |
| 72 | H04 L5 | Fadi Jalabi | Syria | 30.45 | |
| 73 | H04 L1 | Nuno Rola | Angola | 30.68 | |
| 74 | H03 L4 | Patrick Boustany | Lebanon | 30.71 | |
| 75 | H05 L7 | Kabir Walia | Kenya | 30.72 | |
| 76 | H04 L6 | Seung Gin Lee | Northern Mariana Islands | 30.75 | |
| 77 | H04 L8 | Urnultsaikhan Ganbold | Mongolia | 30.80 | |
| 78 | H04 L2 | Sean Chow | Fiji | 30.84 | |
| 79 | H03 L3 | Clark Randrianandraina | Madagascar | 31.55 | |
| 80 | H02 L4 | Welbert Samuel | Federated States of Micronesia | 31.80 | |
| 81 | H02 L5 | Peter James Linch | Zambia | 32.08 | |
| 82 | H03 L2 | Muzeya Muzyamba | Zambia | 32.32 | |
| 83 | H03 L1 | Sarmad A.A. Mohamad | Iraq | 32.90 | |
| 84 | H02 L6 | Carlos Notarianni | Marshall Islands | 33.12 | |
| 85 | H03 L8 | Mohammed S. Abbas | Iraq | 33.21 | |
| 86 | H05 L2 | Hadjamamed Hadjamamedov | Turkmenistan | 33.85 | |
| 87 | H02 L2 | Awsan Mohammed Saleh Qardaa | Yemen | 45.91 | |
| 88 | H02 L7 | Ali Maiga Akibou | Niger | 47.50 | |
| - | - | Gilbert Kaburu | Uganda | DQ | |
| - | - | James Goddard | Great Britain | DNS | |
| - | - | Peter Mankoč | Slovenia | DNS | |
| - | - | Fils Theodore Tchena | Cameroon | DNS | |
| - | - | Zhmed Ouattara Zie | Ivory Coast | DNS | |
| - | - | Landry H. Degnifo Enokorin | Ivory Coast | DNS | |
| - | - | Abubakarr Ialloh | Sierra Leone | DNS | |
| - | - | Nkandeu Fortin Leukam | Cameroon | DNS | |
| - | - | Emery Nziyumvira | Burundi | DNS | |