Microsoft responded to the reports by calling for a full review of the facts.
"We take all allegations brought to our attention seriously, and we cooperate fully in any government inquiries," Microsoft deputy general counsel John Frank said in a blog post.
"The matters raised in the Wall Street Journal are important, and it is appropriate that both Microsoft and the government review them."
Frank said that "like other large companies with operations around the world, we sometimes receive allegations about potential misconduct by employees or business partners, and we investigate them fully, regardless of the source."
The report said the US Department of Justice and the Securities and Exchange Commission are investigating a claim by an anonymous former Microsoft representative in China that kickbacks were used to get business there.
Allegations being explored reportedly include bribes being made in Romania and gifts lavished on government procurement officials in Italy.
The Journal cited unnamed sources. US officials declined to comment on the report to the daily.
For the latest tech news and reviews, follow Gadgets 360 on X, Facebook, WhatsApp, Threads and Google News. For the latest videos on gadgets and tech, subscribe to our YouTube channel. If you want to know everything about top influencers, follow our in-house Who'sThat360 on Instagram and YouTube.