Olympian Minh defeated Ihsan Maulana Mustofa of Indonesia 21-15, 21-15 in just 39 minutes.
Minh is world No 73, while Mustofa is world No 44.
The HCM City-born player came from behind to beat Sourabh Verma of India 18-21, 21-15, 21-11 in the second round and overcame Tanangsak of Thailand in the first round.
Singapore Open is a World Tour Super 500 tournament held since 1987 in Singapore. It is one of only seven Super 500 tournaments on the Tour, with the others being hosted in Hong Kong, India, Indonesia, the Republic of Korea, Malaysia and Thailand.
This year's event is taking place from July 17-22.