Ms Cheney, the third highest-ranking Republican leader in the House, voted to impeach Mr Trump for an historic second time over his role in the 6 January Capitol riot and has since become a target for the former president and his supporters.
Now, the Wyoming congresswoman has hit back on social media at his latest claims.
“The 2020 presidential election was not stolen. Anyone who claims it was is spreading THE BIG LIE, turning their back on the rule of law, and poisoning our democratic system,” tweeted Ms Cheney.
On Friday right-wing news network Newsmax issued a public apology to Dominion Voting Systems employee Eric Coomer, and admitted it had “no evidence” of claims it made that he had manipulated voting machines.
Mr Coomer launched a defamation lawsuit last December against Newsmax, One America News Network, OANN correspondent Chanel Rion, Rudy Giuliani, Sidney Powell and others, for claims they made against him after the election.
House Republicans have accused Ms Cheney of dividing the GOP conference with her criticism of Mr Trump.
Ms Cheney is the House Republican Conference Chair, the third-highest position in the House Republican leadership, and some lawmakers have threatened to try and remove her.
She already survived a similar vote earlier this year and it is unclear if House GOP Leader Kevin McCarthy will bring another one against her.