Xiaomi, which is looking to gain ground on rivals Apple, Huawei and Samsung, revealed the flagship product at a launch event at the Barbican Centre.
The Mi 8 Pro will go on sale in Britain on Friday, the group announced, marking the first time that the device has been available outside China.
The phone, which retails from £499.99 ($657, 573 euros), uses Google's Android operating system and has a fingerprint sensor in its 6.2-inch screen. It will be available from various outlets including operator Three Mobile.
Xiaomi also announced it will open an official Mi Store on November 18 at London's Westfield shopping centre in White City, having opened in Paris earlier this year.