Marc Brian Louis of Singapore claimed silver with Malaysia's Muhammad Haiqal Hanafi winning bronze.
Soraoat, who also won the 200m four days earlier, was quick to acknowledge the absence of his compatriot and teen sprint sensation and defending champion, Puripol Boonson, from the race.
"There was so much pressure before the start,” said the 21-year-old. “The whole weight was on me. It was unusual for me because in these types of races, Puripol (Boonson) was always there.
"In the end I got the 200m and now the 100m and a silver (in the 4x100m). So maybe this SEA Games is my time to shine but I want Puripol to come back soon so we can get back to running together again."
The man labelled ‘the fastest man in Southeast Asia’, Lalu Muhammad Zohri did not start.
SEA Games 2023 – men’s 100m sprint results
1 Soraoat Dapbang THA 10.37
2 Marc Brian Louis SGP 10.39
3 Muhammad Haiqal Hanafi MAS 10.45