Lei Jun, chairman and CEO of Xiaomi, demonstrates the Xiaomi 4 smartphone at a launch event in Beijing on July 22, 2014. Photo: IC

China's Xiaomi Technology Co Ltd made a profit of 347.48 million yuan ($56.16 million) from revenue of 26.58 billion yuan ($4.29 billion) in 2013, according to a filing that Midea Group Co Ltd released on Monday.

The earnings results were included in disclosures made to the Shenzhen Stock Exchange after Xiaomi purchased a 1.3 percent stake in Midea Group, a publicly traded electrical appliance company, for 1.27 billion yuan.

The filing showed the razor-thin margins at one of the handset industry's fastest-growing companies.

The filings also revealed chairman and CEO Lei Jun claims 77.8 percent ownership of the company he co-founded in 2010, while unnamed shareholders split the remaining shares.

The regulatory document provides for the first time an official snapshot of a company that became the most popular smartphone vendor in China and the third-largest vendor in the world this year, thanks to a lineup of handsets that are considered high-quality yet relatively inexpensive.

Xiaomi has long branded itself an "Internet company" that eschews traditional marketing and sells hardware at low prices as a distribution channel for its real moneymaker: software and services. But the financial impact of its business model - and whether it can generate sustainable profits demanded by public markets - has been a subject of long-running speculation in the technology industry.

With operating profits of 485.77 million yuan in 2013, Xiaomi's operating margins of less than 2 percent lagged far behind the two market leaders, Apple Inc and Samsung Electronics Co Ltd, the filing showed.

In 2013, Samsung's mobile division reported 18.7 percent operating margins while Apple reported 28.7 percent for the fiscal year ended in September 2013.

A Xiaomi spokeswoman confirmed the accuracy of the filing.

All but leading smartphone makers Samsung and Apple will see profitability dwindle in the coming years due to pricing pressure from companies like Xiaomi, Fitch Ratings warned last month.

Bryan Wang, an analyst at Forrester Research, said Xiaomi's thin margins did not come as a surprise.

"They're growing so fast and so lean, I wouldn't be surprised even if they were losing money," Wang said.

"Every company is trying to match the Xiaomi price," he noted, "The current market is so competitive that I don't think it's sustainable without consolidation."