Five of the participants from Pledis Entertainment were eliminated and only Zhou and Lim Na-young became part of the final line-up for the girl group I.O.I.

They debuted on May 28, 2018, with the single album, Like a V.[10] Zhou released a soundtrack for the television show I Got You, titled "Leave It to Brother".

[11] On August 31, Pledis Entertainment confirmed that Zhou would be making her solo debut in China with digital single, "Why", on September 6.

[14] In October, it was confirmed that Zhou would make her acting debut in the historical mystery drama Miss Truth.

[17] On February 14, 2020, after the premier of Miss Truth, Zhou released the OST for the show, "小窃喜" and "天籁".

[20] On May 4, 2021, Zhou and the members of I.O.I celebrated their 5th debut anniversary with a reunion live stream show called "Yes, I Love It!".