According to the Washington Post, the tech giant found that Russian operatives spent tens of thousands of dollars on ads on YouTube, Gmail, the Google search engine and other products.
The operation could point to a wider Kremlin disinformation campaign than was previously suspected as the ads do not appear to have come from the same troll farm that bought ads on Facebook.
Google, owned by Alphabet Inc, runs the world’s largest online advertising business and YouTube is the world’s largest online video site.
The company did not immediately comment on the claims.
Google had previously played down suggestions of Russia using its platforms to influence the democratic process abroad.
But after launching a review, the company found around $100,000 (£76,000) in ad spending potentially linked to Russian sources, according to a source.
Twitter and Facebook have said Russia bought ads and had accounts on their platforms.
Facebook reportedly unearthed $100,000 (£76,000) in spending from a single Russian group, the Internet Research Agency.
Meanwhile, Congress has started multiple investigations into Russian interference in the 2016 election, with lawmakers on both sides saying Russia intended to sow discord in the US, spread propaganda and sway the election to elect Donald Trump.
Google officials are expected to testify publicly before both the House and Senate intelligence committees on 1 November alongside Facebook and Twitter about Russian attempts to use their platforms to influence the election.