Hugo Barra, the executive charged with leading Xiaomi's international expansion after being poached from Google in 2013, will leave the Chinese high-tech group at a critical time in the company.
In a Facebook post on Monday, Barra, who was Xiaomi's vice-president of international, praised the "rockstar start-up" but said the role had impacted his health.
"What I've realized is that the last few years of living in such a singular environment have taken a huge toll on my life and started affecting my health," Barra wrote.
"My friends, what I consider to be my home, and my life are back in Silicon Valley, which is also much closer to my family. Seeing how much I've left behind these past few years, it is clear to me that the time has come to return."
Barra said he would transition out of his role in February after the Chinese New Year and take some "much-needed time off before embarking on a new adventure back in Silicon Valley". He has been with the firm for three-and-a-half years.
The executive's departure comes at a difficult time for Xiaomi as it faces questions over growth. In a letter to staff this month, Xiaomi chief executive Lei Jun admitted the company had grown "too fast".