French Open, Vinci was upset in the first round by world No. 65, Kateryna Bondarenko, 6–1, 6–3. Vinci played only one grass-court warm-up tournament before Wimbledon. Seeded second at Eastbourne, she lost in the second round to Ekaterina Makarova 6–4, 4–6, 3–6. Seeded sixth at Wimbledon, Vinci reached the third round defeating Alison Riske and lucky loser Duan Yingying. She lost then to 27th seed CoCo Vandeweghe in straight sets. Vinci started her US Open Series at the Canadian Open. Seeded seventh, she lost in the third round to world No. 33, Daria Kasatkina, 5–7, 3–6. Representing Italy at the Rio Olympics, Vinci was defeated in the first round by Anna Karolína Schmiedlová, 7–5, 6–4. Seeded sixth at the Western & Southern Open, Vinci was defeated in the third round by ninth seed Carla Suárez Navarro, 6–1, 7–5. Seeded second at the Connecticut Open, Vinci lost in the quarterfinals to qualifier Johanna Larsson 6–7, 1–6. Vinci was seeded seventh at the US Open, where she has finalist points to defend from last year. She reached the quarterfinals for the fourth time in five years, defeating Anna-Lena Friedsam, Christina McHale, Carina Witthöft, and Lesia Tsurenko. Vinci then lost in the quarterfinals to second seed and eventual champion Angelique Kerber, 5–7, 0–6. As a result, Vinci failed to defend her finalist points from last year, so she fell from the top 10. Seeded 13th at the Wuhan Open, Vinci was defeated in the second round by Yaroslava Shvedova, 7–5, 6–2. Seeded 13th at the China Open, she lost in the second round to Caroline Wozniacki, 3–6, 2–6. Vinci's final tournament of the year was the WTA Elite Trophy in Zhuhai. Seeded fifth, Vinci lost her first match to 9th seed Barbora Strýcová, 4–6, 3–6. In her final match, Vinci was defeated by third seed and eventual champion Petra Kvitová, 6–1, 6–2. In November, Vinci was contemplating retirement from Tennis due to her poor results and tiredness. However, on 21 November 2016, Vinci decided to play at least one more year. Vinci ended the year ranked 18. 2017 Vinci began the season at the Brisbane International. Seeded eighth, she started the tournament off by beating lucky loser Kateryna Bondarenko in the first round, 7–6, 6–7, 7–6. She then defeated Misaki Doi in the second round 6–4, 6–2. In the quarterfinals, Vinci lost to third seed and eventual champion Karolína Plíšková, 6–3, 2–6, 2–6.