| ITF - W25 Hua Hin | 10/14 02:55 | 27 | Mananchaya Sawangkaew v Zhuoxuan Bai | 2-6,4-6 | |
| ITF - W25 Hua Hin | 10/13 04:50 | 26 | Mananchaya Sawangkaew v Natalia Siedliska | 6-3,6-2 | |
| ITF - W25 Hua Hin | 10/11 09:55 | 25 | Lesley P Kerkhove v Mananchaya Sawangkaew | 4-6,4-6 | |
| ITF - W25 Hua Hin | 10/08 03:55 | 28 | Mananchaya Sawangkaew v Zhuoxuan Bai | 1-6,1-6 | |
| ITF - W25 Hua Hin | 10/07 07:30 | 27 | Mananchaya Sawangkaew v Ekaterina Reyngold | 6-4,6-1 | |
| ITF - W25 Hua Hin | 10/06 05:30 | 26 | Mananchaya Sawangkaew v Emily Welker | 7-6,6-7,7-6 | |
| ITF - W25 Hua Hin | 10/04 03:25 | 25 | Peangtarn Plipuech v Mananchaya Sawangkaew | 6-3,3-6,4-6 | |
| ITF - W15 Chiang Rai | 06/19 02:00 | 29 | Mananchaya Sawangkaew v Naho Sato | 4-6,2-6 | |
| ITF - W15 Chiang Rai | 06/18 04:40 | 28 | Punnin Kovapitukted v Mananchaya Sawangkaew | 2-6,3-6 | |
| ITF - W15 Chiang Rai | 06/17 02:00 | 27 | Mananchaya Sawangkaew v Patcharin Cheapchandej | 7-6,5-7,6-3 | |
| ITF - W15 Chiang Rai | 06/16 07:10 | 26 | Mananchaya Sawangkaew v Kamonwan Buayam | 6-1,6-2 | |
| ITF - W15 Chiang Rai | 06/15 01:50 | 25 | Gozal Ainitdinova v Mananchaya Sawangkaew | 3-6,2-6 | |
| ITF - W15 Norman | 10/13 17:30 | 25 | Mia Kupres v Mananchaya Sawangkaew | 6-4,7-6 | |
| ITF - W15 Lubbock | 10/02 17:00 | 28 | Adriana Reami v Mananchaya Sawangkaew | 6-1,3-6,7-6 | |
| ITF - W15 Lubbock | 10/01 16:30 | 27 | Mananchaya Sawangkaew v Layne Sleeth | Retired | |
| ITF - W15 Lubbock | 09/30 15:00 | 26 | Mananchaya Sawangkaew v Ayumi Miyamoto | 6-0,6-1 | |
| ITF - W15 Lubbock | 09/29 17:00 | 25 | Mananchaya Sawangkaew v Carmen Corley | 6-3,6-3 | |
| ITF - W25 Fort Worth | 09/20 14:00 | 54 | Mananchaya Sawangkaew v McCartney Kessler | 6-7,2-6 | |
| ITF - W25 Jodhpur | 02/20 06:05 | 26 | Berfu Cengiz v Mananchaya Sawangkaew | 6-0,7-5 | |
| ITF - W25 Jodhpur | 02/19 08:35 | 25 | Ekaterina Nikiforova v Mananchaya Sawangkaew | 4-6,4-6 | |
| WTA - Hua Hin | 02/08 09:40 | 45 | Chihiro Muramatsu v Mananchaya Sawangkaew | 3-6,6-0,6-3 | |
| ITF - W25 Nonthaburi | 02/05 05:40 | 25 | Bibiane Schoofs v Mananchaya Sawangkaew | Retired | |
| ITF - W25 Nonthaburi | 02/04 02:30 | 44 | Mananchaya Sawangkaew v Ying Zhang | 4-6,6-3,10-6 | |
| ITF - W25 Nonthaburi | 02/03 04:35 | 44 | Mananchaya Sawangkaew v Jiho Shin | 6-3,6-0 | |
| ITF - W25 Nonthaburi | 02/02 08:25 | 44 | Mananchaya Sawangkaew v Maria Filimonikhina | 6-0,6-0 | |
| ITF - W25 Nonthaburi | 01/29 04:20 | 25 | Mananchaya Sawangkaew v Leonie Kung | 6-4,2-6,3-6 | |
| ITF - W25 Nonthaburi | 01/28 02:30 | 44 | Katarzyna Kawa v Mananchaya Sawangkaew | 2-6,2-6 | |
| ITF - W25 Nonthaburi | 01/27 02:30 | 44 | Ying Zhang v Mananchaya Sawangkaew | 3-6,2-6 | |
| ITF - W25 Nonthaburi | 01/26 03:50 | 44 | Natthapat Piwbangruk v Mananchaya Sawangkaew | 2-6,1-6 | |
| ITF - W25 Pune | 12/09 05:30 | 54 | Mananchaya Sawangkaew v Punnin Kovapitukted | 1-6,7-6,10-12 |
Mananchaya Sawangkaew (Thai: มนัญชญา สว่างแก้ว; born 10 July 2002) is a tennis player from Thailand.
She has a career-high singles ranking of 247 by the Women's Tennis Association (WTA), achieved on 4 December 2023. Sawangkaew has won two singles titles and one doubles title on the ITF Women's Circuit.
On the ITF Junior Circuit, she achieved a career-high combined ranking of 14, on 28 January 2019. She reached the quarterfinals of the girls' singles draw at the 2019 Australian Open.
Sawangkaew made her debut for Thailand Fed Cup team in 2019.