"There's no evidence of collusion" between Trump associates and Russia in the campaign, Conway added.
ABC News chief anchor George Stephanopoulos pressed Conway on the fact that Donald Trump Jr. went to the meeting with Russian attorney Natalia Veselnitskaya on June 9, 2016, expecting to be given information helpful to his father's campaign.
"Isn't that at minimum an attempt at collusion?" Stephanopoulos asked.
"Are you saying there's evidence of collusion? Because everybody is trying to convert wishful thinking into hard evidence, and they haven't been able to do that," she said.
Stephanopoulos also asked Conway about her earlier statements that there were no meetings between the campaign and Russians.
"Why did the administration allow those denials to stand for so many months?" he asked.
"Some of the disclosure forms have been amended since that time to reflect other meetings," including the meeting between Donald Trump Jr. and Veselnitskaya, she said.
Donald Trump Jr.; the president's son-in-law, Jared Kushner; and Donald Trump Sr.'s then–campaign chairman, Paul Manafort, met with Veselnitskaya, a lawyer with ties to the Kremlin, at Trump Tower in New York City.
"I was asked to have a meeting by an acquaintance I knew from the 2013 Miss Universe pageant with an individual who I was told might have information helpful to the campaign," Donald Trump Jr. said in a statement. "I was not told her name prior to the meeting. I asked Jared and Paul to attend but told them nothing of the substance.
"We had a meeting in June 2016. After pleasantries were exchanged, the woman stated that she had information that individuals connected to Russia were funding the Democratic National Committee and supporting Ms. Clinton.
"Her statements were vague, ambiguous and made no sense. No details or supporting information was provided or even offered. It quickly became clear that she had no meaningful information," Donald Trump Jr. said.
The meeting with Veselnitskaya was only recently disclosed by Kushner, now a senior White House aide, when he resubmitted a form necessary for his security clearance. Kushner's attorney Jamie Gorelick released a statement on Saturday regarding the revelation, explaining, "As we have previously stated, Mr. Kushner's SF-86 was prematurely submitted and, among other errors, did not list any contacts with foreign government officials."