[1] It was the nation's largest delegation sent to the Olympics in a non-boycotting edition, and the second-largest overall in history, beating the record of 18 athletes who attended the London Games in 2012.

Eight athletes on the Vietnamese roster previously competed in London, with the rest of the field making their Olympic debut in Rio de Janeiro.

Among the nation's athletes were pistol shooter and London 2012 fourth-place finalist Hoàng Xuân Vinh, world-ranked swimmer and 2014 Youth Olympic champion Nguyễn Thị Ánh Viên, weightlifter Trần Lê Quốc Toàn, and sabre fencer and two-time Southeast Asian Games titleholder Vũ Thành An, who was selected by the committee to carry the Vietnamese flag at the opening ceremony.

[13] Ngưng participated on 12 August in the Men's 20 km walk event, finishing 60th out of 63rd competitors on a route along Pontal and failing to advance to the quarterfinals.

[16][17] On 15 August, she ran her heats in 57.87 seconds and finished at the penultimate position in the Women's 400 m hurdles event, only ahead of Natalya Asanova from Uzbekistan.

[17][18][19] Vietnam had two qualified badminton players, Nguyễn Tiến Minh and Vũ Thị Trang, for the following events in the Olympic tournament.

[30][32] Despite finishing in second in the Group J and failing to advance to the Round of 16, Trang still fulfilled her personal goal of getting a winning match.

[33] Minh competed in the Group E in the Men's singles events, starting with the three-game match against Russia's Vladimir Malkov on 11 August.

[49] In the Women's foil category, Đỗ Thị Anh lost the final match to New Zealand's Yuan Ping, who was later ruled ineligible to compete because she played under the Chinese jersey.

[49][50] Thị Anh was subsequently selected to replace Ping, as the next highest-ranked fencer, for the Games by the International Fencing Federation in June.

[50][51] Hoa was the first member to compete in the Women's épée event on 6 August, where she lost the match to Auriane Mallo of France with the score of 7–15 and finished last on the final ranking.

[55][56] Thị Anh competed in the Women's foil events on 10 August, starting with the winning match against Aikaterini Kontochristopoulou from Greece with the score of 15–13.

[59] Thị Anh lost her second match to Italy's Arianna Errigo with a score of 9–15, finishing 32nd out of 35th competitors on the final ranking.

[59][58][60] That same day, Thành An also took part in the Men's sabre events, where he won his first match against the 2012 Olympic silver medallist Diego Occhiuzzi of Italy with a score of 15–12.

[62][64] Vietnam entered two artistic gymnasts into the Olympic competition, Phạm Phước Hưng and Phan Thị Hà Thanh.

[76][77] She claimed her spot by being one of the highest-ranked judokas outside of the direct qualifying position in the International Judo Federation World Ranking List, which was announced on 30 May 2016.

[75][78] Despite having unsuccessfully qualifying competitions in the recent months, Tú still had stable cumulative points that helped her stay in the top 50 ranking.

"[81] After the Asia and Oceania Continental Qualification Regatta in Chungju in April 2016, Vietnam has three qualified rowers in two categories for the 2016 Games: Phạm Thị Huệ in the women's single sculls category; Phạm Thị Thảo and Tạ Thanh Huyền in the women's lightweight double sculls.

[89][90] Huyền ended up teaming with Hồ Thị Lý in the women's lightweight double sculls events at the Rodrigo de Freitas Lagoon, starting with the 2000 m rowing regatta on 8 August.

[107][100][101] The shooters were trained in their homeland, the US and South Korea prior to the Games,[106][107] before moving to Olympic Shooting Centre once they arrived at Rio de Janeiro.

[106] Vinh and Cường competed in the men's 10 m air pistol events on 6 August, starting with the qualification round where each shooter fired 60 shots.

[115][116][117] By scoring 202.5 points in the final round of the men's 10 m air pistol, Vinh set a new Olympic record based on the International Shooting Sport Federation Rule changed on 1 January 2013.

"[122] In a congratulations letter to Vinh, Prime Minister Nguyễn Xuân Phúc wrote that his victory "brings honor to the country and pride for officials, coaches, athletes and Vietnamese fans.

[133][135][139] Vietnamese weightlifters qualified three men's quota places for the Rio Olympics based on their combined team standing by points at the 2014 and 2015 IWF World Championships.

[142] That month, Vương Thị Huyền was also chosen for a single women's Olympic spot, added by virtue of a top six national finish at the 2016 Asian Championships.

[147] Tuấn, who had suffered from a recurrent knee injury shortly before the Games,[148] registered for 130 kg and managed to do it on the second try, ranked in fourth in the snatch round.

[154][155] A day before Hằng's opening match in the women's freestyle 48 kg event on 17 August, the delegation's medical department confirmed she had a recurrence of spinal and lumbar injuries.