In Paris at the Open GdF Suez, Koukalová was defeated in the second round by fourth seed and 2012 champion Angelique Kerber. During the Fed Cup tie against Spain, Koukalová won her first rubber over María Teresa Torró Flor, but she lost her second rubber to Carla Suárez Navarro. In the end, the Czech Republic defeated Spain 3–2. At the Qatar Open, Koukalová upset ninth seed Ana Ivanovic in the second round. She was defeated in the third round by sixth seed and eventual finalist Angelique Kerber. As the top seed at the first edition of the Rio Open, Koukalová made it to the final where she lost to fifth seed Kurumi Nara. Seeded third at the Brasil Tennis Cup, Koukalová won the tournament beating second seed Garbiñe Muguruza in the final; this was her third WTA singles title. Seeded 28th at the BNP Paribas Open, Koukalová was defeated in the second round by compatriot Karolína Plíšková. Seeded 27th at the Sony Open Tennis, Koukalová lost her second-round match to Caroline Garcia. Seeded fifth at the Katowice Open, Koukalová made it to the quarterfinal round where she was defeated by fourth seed and eventual champion, Alizé Cornet. In doubles, she and Niculescu reached the final where they lost to Yuliya Beygelzimer/Olga Savchuk.