The smartphone boasts a number of impressive features, including a triple-lens main camera with a 48MP sensor and a 20MP front-facing selfie camera.
Other features include an under-screen fingerprint sensor, Qualcomm's Snapdragon 855 processor, and up to 8GB of RAM.
The company also announced a transparent model of the Mi 9 which sports 12GB of RAM and is modelled after the film Alita: Battle Angel.
Xiaomi also launched its smaller Mi 9 SE device, which is available in two variants starting at around $300.
The Xiaomi Mi 9 with 6GB RAM and 128GB storage will reportedly be priced at $450, while the 8GB version and the "Battle Angel" device could be priced at $490 and $595 respectively.
There is currently no information on international pricing and availability of the Xiaomi Mi 9.