2007 World Championships in Athletics – Women's 400 metres

Qualification: First 4 in each heat (Q) and the next 4 fastest (q) advance to the semifinals.

Rank	Heat	Name	Nationality	Time	Notes
1	4	Novlene Williams	Jamaica	50.21	Q
2	5	Christine Ohuruogu	Great Britain	50.46	Q, SB
3	5	Ilona Usovich	Belarus	50.53	Q, NR
4	4	Ana Guevara	Mexico	50.85	Q
5	1	Natalya Antyukh	Russia	50.88	Q
6	5	Natasha Hastings	United States	51.07	Q
7	1	Mary Wineberg	United States	51.25	Q
8	2	DeeDee Trotter	United States	51.27	Q
9	1	Shereefa Lloyd	Jamaica	51.42	Q
10	1	Lee McConnell	Great Britain	51.44	Q, SB
11	2	Nicola Sanders	Great Britain	51.45	Q
12	2	Joanne Cuddihy	Ireland	51.55	Q, SB
12	2	Christine Amertil	Bahamas	51.55	Q
14	4	Ionela Târlea-Manolache	Romania	51.59	Q
15	3	Tatyana Veshkurova	Russia	51.67	Q
16	3	Shericka Williams	Jamaica	51.72	Q
17	4	Aymée Martínez	Cuba	51.74	Q, PB
18	5	Indira Terrero	Cuba	51.76	Q
19	3	Barbara Petráhn	Hungary	51.86	Q, SB
20	3	Amantle Montsho	Botswana	51.87	Q
21	4	Aliann Pompey	Guyana	51.95	q
22	5	Daniela Reina	Italy	52.02	q, SB
23	4	Christy Ekpukhon Ihunaegbo	Nigeria	52.05	q
24	5	Asami Tanno	Japan	52.13	q, SB
25	2	Zuzanna Radecka	Poland	52.19
26	4	Makelesi Bulikiobo	Fiji	52.23	SB
27	1	Oksana Shcherbak	Ukraine	52.39
28	3	Kineke Alexander	Saint Vincent and the Grenadines	52.51
29	2	Folashade Abugan	Nigeria	52.58
30	5	Gabriela Medina	Mexico	53.16
31	1	Justine Bayigga	Uganda	53.25
32	2	Maria Laura Almirão	Brazil	53.68
33	1	Joy Eze	Nigeria	53.83
34	3	Ginou Etienne	Haiti	53.89
35	4	Solen Désert	France	54.03
36	1	Olga Tereshkova	Kazakhstan	54.09
37	5	Sandrine Thiébaud-Kangni	Togo	54.11
38	3	Amy Mbacke Thiam	Senegal	54.31
39	2	Hazel-Ann Regis	Grenada	54.78	SB
40	3	Nawal El Jack	Sudan	55.29
41	5	Temalangeni Dlamini	Swaziland	58.27	PB
42	2	Vera Barbosa	Cape Verde	58.56

First 2 in each semifinal(Q) and the next 2 fastest(q) advance to the final.

Rank	Heat	Name	Nationality	Time	Notes
1	1	Novlene Williams	Jamaica	49.66	Q, SB
2	2	Nicola Sanders	Great Britain	49.77	Q, PB
3	2	Natalya Antyukh	Russia	49.93	Q, SB
4	3	Christine Ohuruogu	Great Britain	50.16	Q, PB
5	1	Ana Guevara	Mexico	50.19	Q, SB
6	3	Mary Wineberg	United States	50.27	Q
7	2	DeeDee Trotter	United States	50.31	q
7	1	Ilona Usovich	Belarus	50.31	q, NR
9	2	Shericka Williams	Jamaica	50.37	SB
10	3	Tatyana Veshkurova	Russia	50.71
11	1	Joanne Cuddihy	Ireland	50.73	NR
12	3	Amantle Montsho	Botswana	50.90	NR
13	3	Shereefa Lloyd	Jamaica	51.00	PB
14	1	Lee McConnell	Great Britain	51.07	SB
15	1	Indira Terrero	Cuba	51.08
16	2	Christine Amertil	Bahamas	51.18
17	1	Natasha Hastings	United States	51.45
18	3	Christy Ekpukhon Ihunaegbo	Nigeria	51.60
19	3	Ionela Târlea-Manolache	Romania	51.62
20	1	Asami Tanno	Japan	51.81	SB
21	2	Daniela Reina	Italy	51.99	SB
22	2	Barbara Petráhn	Hungary	52.12
23	2	Aliann Pompey	Guyana	53.58
24	3	Aymée Martínez	Cuba	57.77