US intelligence agencies believe Moscow interfered in the White House race by hacking into emails of the Democratic National Committee.
There are suggestions the alleged hacking helped Republican Mr Trump defeat Democrat rival Hillary Clinton in November’s election.
The president-elect, who has questioned the controversial claims, is due to receive an intelligence briefing from spy chiefs on the issue.
In an interview prior to the briefing, he told the New York Times: “China, relatively recently, hacked 20 million government names”, referring to the Office of Personnel Management breach in 2014 and 2015.
Mr Trump added: “How come nobody even talks about that? This is a political witch-hunt.”
He said hackers have infiltrated the White House and Congress, saying: “We’re like the hacking capital of the world.”