Aquatics at the 1983 Southeast Asian Games included swimming, diving and water polo events. The three sports of aquatics were held at Toa Payoh Swimming Complex, Singapore City, Singapore. Aquatics events was held between 29 May to 3 June.

Men's events

Event	Gold		Silver		Bronze
100 m freestyle	Ang Peng Siong	53.58 (rec)	Tay Khoon Hean	54.45	Lukman Niode	54.63
200 m freestyle	William Wilson	1:57.97 (rec)	Lukman Niode	1:58.18	Tay Khoon Hean	1:59.32
400 m freestyle	William Wilson	4:08.94 (rec)	Soo-Tho Kok Mun	4:16.38	Joselito Andaya	4:18.24
1500 m freestyle	Joselito Andaya	16:50.69	Soo-Tho Kok Mun	17:11.39	William Wilson	17:38.00
100 m backstroke	Lukman Niode	59.72 (rec)	David Lim	1:01.54	Judy Jaoud	1:03.97
200 m backstroke	Lukman Niode	2:13.41 (rec)	David Lim	2:14.80	Judy Jaoud	2:19.80
100 m breaststroke	Jairulla Jaitulla	1:08.10 (rec)	Francisco Guanco	1:09.56	Oon Jin Teik	1:10.17
200 m breaststroke	Francisco Guanco	2:29.46 (rec)	Tjatur Sugiarto	2:33.33	Rene Concepcion	2:34.33
100 m butterfly	Ang Peng Siong	57.87 (rec)	Tay Khoon Hean	59.52	John Item	60.34
200 m butterfly	William Wilson	2:10.07	Ridwan Muis	2:12.14	Renato Padronia	2:13.67
400 m individual medley	William Wilson	4:45.72 (rec)	Jairulla Jaitulla	4:50.66	Soo-Tho Kok Mun	4:56.81
4x100 m freestlye relay	Singapore	3:38.42 (rec)	Indonesia	3:43.42	Philippines	3:47.85
4x100 m medley relay	Singapore	4:02.64 (rec)	Indonesia	4:03.62	Philippines	4:09.81
4x200 m freestlye relay	Singapore	8:06.32 (rec)	Philippines	8:06.81	Indonesia	8:13.03

Women's events

Event	Gold		Silver		Bronze
100 m freestyle	Junie Sng	1:01.77	Chan Mui Pin	1:02.13	Helen Chow	1:02.57
200 m freestyle	Junie Sng	2:10.31	May Tan	2:13.36	Chan Mui Pin	2:13.51
400 m freestyle	Junie Sng	4:29.74 (rec)	Elfira Rosa Nasution	4:38.75	Chan Mui Pin	4:39.28
800 m freestyle	Junie Sng	8:59.46 (rec)	Katerina Ong	9:33.92	Elfira Rosa Nasution	9:34.70
100 m backstroke	Christine Jacob	1:10.34	Kwek Leng	1:10.78	Lai May May	1:10.95
200 m backstroke	Christine Jacob	2:29.00 (rec)	Kwek Leng	2:32.81	Helen Chow	2:34.82
100 m breaststroke	Helen Chow	1:18.88	Ee Yan Hui	1:19.72	Lourdes Samson	1:20.01
200 m breaststroke	Kanogwan Sriprasert	2:25.17	Christina Tham	2:56.93	Sandra Melani Maksudi	2:57.35
100 m buttertfly	Junie Sng	1:05.32 (rec)	Helen Chow	1:06.40	May Tan	1:06.86
200 m butterfly	Junie Sng	2:20.35 (rec)	Mavis Ee	2:24.54	Selowati Hadi Sujono	2:28.22
400 m butterfly	Junie Sng	4:29.74 (rec)	Elfira Rosa Nasution	4:38.75	Katerina Ong	4:39.28
400 m individual medley	Junie Sng	5:04.37 (rec)	Elfira Rosa Nasution	5:30.11	Pasawan Phantumabumroong	5:38.97
4x100 m freestlye relay	Singapore	4:11.21 (rec)	Philippines  Thailand	4:15.29
4x100 m medley relay	Singapore	4:39.12 (rec)	Malaysia	4:41.84	Philippines	4:46.89

Event	Gold	Silver	Bronze
Men's	Singapore	Malaysia	Indonesia

Event	Gold		Silver		Bronze
Men's springboard	Kristiadi Permana	490.85	Sangwal Foungdee	454.70	Haryo Ramayana	398.45
Men's placing	Somchai Ongkasing Ong Ka Sing	158.25	Leong Siet Fong	156.35	Richard Tham	155.85
Men's platform diving	Somchai Ongkasing	453.55	Eko Setiadi	440.65	Richard Tham	415.60
Women's springboard	Indah Siantiningsih	308.80	Dwi Setyowati	294.86
Women's placing	Indah Siantiningsih	167	Dwi Setyowati	166	Lee Po Ling	159.45
Women's springboard diving	Indah Siantiningsih	373	Dwi Setyowati	331.50	Lee Po Ling	322

Rank	Nation	Gold	Silver	Bronze	Total
1	Singapore (SIN)	16	12	9	37
2	Philippines (PHI)	9	4	10	23
3	Indonesia (INA)	6	12	8	26
4	Thailand (THA)	3	2	1	6
5	Malaysia (MAS)	2	6	5	13
Totals (5 entries)		36	36	33	105

• https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19830530-1.2.106
• https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19830531-1.2.123
• https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19830601-1.2.137
• https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19830602-1.2.102