The group's CEO, Javier Palomarez, met personally with Trump last month to secure the date for the Q&A, the organization said.
The cause of the withdrawal, according to the USHCC, which represents Hispanic-owned businesses, was that Trump didn't like the format and worried about the questions and some reporters in attendance.
"Mr. Trump was unwilling to abide by the terms and conditions of the USHCC's Presidential Candidate Q&A Series -- the same rules that all participants have previously followed," Palomarez said in a statement. "The USHCC refused to change the format of the forum, show any favoritism, exclude any issues or topics, or grant any immunity from objective scrutiny of his policies."
The Trump campaign responded today that the presidential candidate will instead be speaking in Nevada at a campaign rally, and alleged that USHCC requested Trump join the chamber "for a fee amounting to between $25,000 and $2 million, which Mr. Trump refused to do."
The USHCC responded that such accusations are a lie and that it never raised the subject of Donald Trump joining the association.
"Trump’s statement on sponsorship is a lie -- he asked if we would consider [Trump National] Doral [Hotel] for our Miami convention. We said no. We’ve also severed business relations with him indefinitely," Palomarez told ABC News today.
Trump has repeatedly declared Hispanics would love him because he'd get jobs back in America, but the USHCC denounces the sudden withdrawal as showing a lack of respect towards Hispanics.
"Withdrawing from the Q&A can only suggest that Trump himself believes his views are indefensible before a Hispanic audience," Palomarez said.
"As it relates to immigration, our objective was to refocus the national debate toward the more positive, fact-based, and economically sound narrative that the USHCC has been advancing for years, long before the 2016 election cycle," Palomarez said. "With an 84 percent disapproval rating among Hispanics, Trump's decision to withdraw from the session only deepens our community's already negative perceptions of him."
"We don't agree on everything certainly but I think I agreed to do some kind of luncheon or whatever down in Washington," Trump said. Palomarez "is having the meeting down in Washington. So, I will be going down at some point in October or whatever. I will go to Washington. That won't be that easy a meeting because you'll have hundreds of people and they will have constituents of his and they may disagree with me but ultimately we will all get along."
USHCC Communications Director Ammar Campa-Najjar told ABC News that the organization knew Trump was getting cold feet, but actually found out about the withdrawal from an inquiry they received from a media outlet.
One of the questions he was uncomfortable with included his plan on mass deportation, Campa-Najjar said.
"We were going to ask him about his own immigration plans. He cites undocumented immigrants get $4.2 billion a year in tax credits, yet estimates show his own plan to deport 11 million in two years would cost $400 billion," Campa-Najjar explained. "These people have to live 100 years to incur the cost of his two-year plan and he was uncomfortable answering those questions."
Ramos was kicked out of a Trump news conference in August for trying to ask a question.