Microsoft has confirmed that officials from China's State Administration for Industry and Commerce - the body responsible for enforcing business laws - have visited some of its offices.
The firm, which has not been accused of any wrongdoing, did not disclose the reason for the visits.
But media reports indicate the technology giant may be facing a potential anti-trust investigation.
Microsoft said "it will address any concerns the government may have".
Any potential investigation in China would be a fresh setback for Microsoft in the country, a key growth market for global technology firms.
Earlier this year, China said it would ban government use of Windows 8, Microsoft's latest operating system.
Increased scrutiny?
The visits to Microsoft offices come just days after the China's anti-trust regulator said that Qualcomm, one of the world's biggest mobile chipmakers, had used monopoly power in setting its licensing fees.
The anti-trust case has already seen some local handset makers hold back on signing licences for Qualcomm products, hitting its revenues.
Another technology firm, Interdigital - which specialises in wireless technology, has also faced a similar investigation.
Chinese regulators suspended that investigation earlier this year after Interdigital agreed to change its pricing structure.
However, some have alleged that China is using anti-trust probes to protect domestic firms.
"It has become increasingly clear that the Chinese government has seized on using the [anti-monopoly] law to promote Chinese producer welfare, and to advance industrial policies that nurture domestic enterprises," the US Chamber of Commerce said earlier this year.