On August 7, Hernandez competed in the Women's Qualification at the 2016 Summer Olympics. She scored a 15.200 on the vault, a 15.366 on the balance beam, and a 14.800 on the floor exercise, qualifying to the balance beam event finals. On August 9, the US team, known as the Final Five, won the gold medal in the Team All Around. On August 15, Hernandez won a silver medal in the Balance Beam event final with a score of 15.333. She placed ahead of teammate Simone Biles, who placed 3rd and behind Sanne Wevers of the Netherlands, who won gold.
By winning the gold medal in the Team All Around, Hernandez became the first athlete born in the 21st century to win an Olympic gold medal.