Her signature playing style entails lethal shovel serves, fast short-pimpled backhand punches, and flat forehand smashes.

[16] In March 2015, she won, after beating Shan Xiaona, Che Xiaoxi and Feng Tianwei, the singles' title at German Open against Petrissa Solja.

[17] On 5 July 2015, Mima Ito and Miu Hirano won the Women's Doubles title at the ITTF World Tour on the Korea Open in the city of Incheon.

The triple crown is the third in the history of the All Japan Table Tennis Championships after Kazuko Yamaizumi (1960) and Kasumi Ishikawa (2014), and she was the youngest to achieve this feat at the age of 17 years old.

[26] In May, in the 2018 World Team Table Tennis Championships, she defeated Jeon Ji-hee 3–0 in the semifinals[27] and Liu Shiwen, who has won 37 consecutive victories against Japanese players, in the first match in the final.

[28] In January 2020, it was announced that Ito Mima would be part of the women's table tennis team for the 2020 Tokyo Olympics, together with Kasumi Ishikawa and Miu Hirano.

[30] In March 2020, Ito Mima and Jun Mizutani won the Mixed Doubles category at the Qatar Open, beating Chinese pair Sun Yingsha and Wang Chuqin 3–1 in the finals.

[31] In November 2020, she won the bronze medal in the 2020 Women's World Cup, losing to Sun Yingsha in the semifinals, but beating Han Ying in the 3rd–4th place match.

[45] In an interview in late June, Ito stated that she was ready to play even if the Olympics were to be held the next day, and that she was hoping to take home three gold medals in Tokyo.

In the quarter-finals against Germany’s Patrick Franziska and Petrissa Solja, Ito and Jun advanced by prevailing in the seventh set 16–14 after saving seven match points.

Ito was praised for her aggressive play as critical in their comeback 4–3 finals win (after initially trailing 2–0) over the number one-ranked pair of China's Liu Shiwen and Xu Xin.

Her teammates Ishikawa and Hirano won the first game in the opening doubles however their lead was soon wiped out after Chen Meng and Wang Manyu had gained ground, winning 9–11, 11–6, 11–8, 11–7.

Ito's team eventually lost the game after Wang beat Hirano 11–5, 11–9, 11–3 in the third match with the total score of 0–3 losing to China and consequently taking the Silver medal.

Deng Yaping also praised Ito's tendency to mount comebacks based on her willingness to take risks and swing at difficult shots when she is losing by a lot.

[76] In 2018, she appeared in the music video of Little Glee Monster's single "Sekai wa Anata ni Waraikakete Iru" (世界はあなたに笑いかけている; "The World Is Smiling at You".