It's safe to say Jennifer Lopez isn't settling for the bare minimum when it comes to romance ... 'cause if you're planning to slide into her DMs, don't bother.

J Lo was on "Watch What Happens Live" when Andy Cohen asked her whether a guy could shoot his shot by messaging her on Instagram ... and her answer came fast -- a hard "no."

Check out the clip ... J Lo's reaction says it all. She looks completely unimpressed by the idea, adding that if someone really wanted to get in touch with her, they'd find a way.

Andy even tried to sweeten the deal by suggesting the mystery DM sender could be a hot Spanish soccer player -- a timely question with the upcoming World Cup -- but J Lo wasn't buying it for a second.

As we reported, J Lo recently shut down rumors she was dating her "Office Romance" costar Brett Goldstein, following her divorce from her fourth husband Ben Affleck.

So if you're hoping to land Hollywood's most eligible bachelorette, forget the lazy DM, the late-night "u up?" text, and the half-hearted coffee invite ... J Lo's making it crystal clear you're gonna have to come with a whole lot more effort!!!