In a joint press conference with French President Emmanuel Macron, Trump called Xi a friend and a great leader he respects.
"He's a very talented man. I think he's a very good man. He loves China, I can tell you. He loves China. He wants to do what's right for China," Trump said in Paris.
He also said France and the U.S. are "forever joined together by the spirit of revolution and the fight for freedom."
But Trump's positive comments are at odds with renewed criticism of the Chinese government after the death of Liu, who had been a leading figure in the push for democracy and human rights in China.
German Chancellor Angela Merkel said in a statement that Liu had been a "courageous fighter for civil rights and freedom of expression."
Earlier Thursday, Chinese authorities said Liu died at the age of 61 from multiple organ failure. He had not been allowed to leave China to treat his late-stage liver cancer, as he had repeatedly asked to do.
Artist and fellow dissident Ai Weiwei told Reuters on Thursday that with Liu's death, "China showed how brutal its society can be."