Jason and Kylie Kelce were seemingly trying to have a low-key date night when it was interrupted by a fan in need of a lesson in manners ... 'cause the Philadelphia Eagles legend's wife was forced to confront a woman in a heated exchange.

A brief clip of the interaction was captured and posted on social media ... with Philly-based podcast "Word to the Wise" claiming the married couple was minding their business when they were stopped by someone wanting a picture outside Steve & Cookies in New Jersey.

The outlet cited multiple witnesses who are adamant the Kelces politely declined the photo-op ... but the woman didn't take it lightly as she approached them and started yelling.

The vid shows Kylie and the woman going at it within inches of each other's faces ... when a man steps in between them to try and break it up.

Jason, meanwhile, is spotted standing several feet away ... keeping a close eye on the action.

At one point, the woman appears to say something along the lines of the Kelces never being allowed back in the area again over the matter.

Kylie fired back -- and it sounds like she says, "I can smell the alcohol on your breath, you're embarrassing yourself," although some viewers believe she simply said "Save your breath, you're embarrassing yourself."