A real estate company with ties to first son Hunter Biden received more than $100 million from a Russian billionaire for property investments across the US that date back a decade, sources have told The Post.

The hefty cash injections into Rosemont Realty came from Elena Baturina — one of Russia’s wealthiest women, the widow of the former mayor of Moscow, and a close ally of Moscow tyrant Vladimir Putin, the sources said.

In one portfolio deal, Baturina paid at least $40 million to Rosemont to invest in office buildings across the country, according to a source with knowledge of the transactions.

That money went toward the 2012 purchase of seven office buildings in Texas, Colorado, Alabama, New Mexico and Oklahoma, according to deal-related emails obtained by DailyMail.com.