"Chinese smartphone maker Xiaomi has become the world's most valuable technology start-up just four years after it was founded."
The firm raised $1.1bn (£708m) in its latest round of funding, giving it a valuation of $45bn, which surpassed the $40bn value of taxi booking app Uber.
It has quickly risen to the ranks of the world's biggest smartphone makers, behind Samsung and Apple in sales.
The company is also set to unveil a new flagship device in January.
Xiaomi's investors include private equity funds All-Stars Investment, DST Global, Hopu Investment Management, Yunfeng Capital, and Singapore sovereign wealth fund GIC, said co-founder and president Bin Lin in a Facebook post.
"This is an affirmation of Xiaomi's stellar results in four years, and heralds a new phase for the company," Mr Bin said.
Read more: On the fast track: Xiaomi's strategy of producing cheap smartphones has catapulted its growth to overtake giant Samsung