The DNC just released a portion of the former First Lady's speech for Monday night's Democratic National Convention. She pretaped it, because remember ... it's all virtual this year ... and in the clip, she praises Biden as a man of faith who will tell the truth and trust science.

She never says Trump's name, but the references are clear -- the Prez is frequently accused of not believing scientists, like Dr. Anthony Fauci or Dr. Deborah Birx ... accused of lying, and absurdly said Joe Biden wanted to "hurt God."

Michelle's used to taking center stage at the DNC ... she was there just 4 years ago, and delivered a rousing speech stumping for Hillary Clinton.

You'll recall Michelle made these words famous at the 2016 convention -- "When they go low, we go high." Remains to be seen if she'll drop another anthem in this year's speech.

Former Ohio Gov. John Kasich, a Republican, is expected to address the DNC tonight -- and a former senior administration official under Trump endorsed Biden today, saying he'd seen Trump do "terrifying" things as Chief Executive.

NY Gov. Andrew Cuomo, former Presidential candidate Amy Klobuchar, Michigan Gov. Gretchen Whitmer and Sen. Bernie Sanders are all expected to take the stage too.

BTW ... Eva Longoria is hosting tonight's online DNC festivities.