JENNIFER ANISTON has banned her own mother from her upcoming wedding!

The screen beauty exploded because her ailing 76-year-old mom Nancy Dow STILL can’t manage to keep her mouth shut about her famous daughter’s private life, say sources.

“Being at Jennifer’s wedding to Justin was one of Nancy’s greatest late-in-life dreams – but now that dream is shattered,” declared an insider.

The two have been feuding off and on for years – ever since Nancy blabbed too much about Jennifer’s personal matters in a 1996 TV interview. But the rift had been healed recently, and Nancy was looking forward to seeing Jennifer, 43, walk the aisle with her 41-year-old actor/screen­writer fiance Justin Theroux.

But when Nancy started asking a bunch of questions about the upcoming event, it set off an alarm in Jennifer’s head. She realized her mom was gossiping way too much about her wedding plans.

Now she has banned Nancy from the nuptials – just like she banned her from her wedding to Brad Pitt back in 2000.

Jennifer and Nancy reconciled after the former “Friends” star split from Pitt in 2005, and the actress quietly provided financial support for her mom, who broke her hip in a 2010 fall and suffered a devastat­ing stroke last year.

But Nancy continues to infuriate Jennifer.

As The ENQUIRER revealed, only days after Jennifer and Justin announced their engagement on Aug. 10, Nancy dropped a bombshell, telling friends that Jen is pregnant and planning a shotgun wedding in Mexico.

The couple has actually enter­tained a number of locales for the nuptials, including Greece and Paris. Most recently, it’s been reported that they’ll tie the knot in Kenya this December and possibly arrange another celebration later on in L.A.

“After her star-studded $1 million wedding to Brad, Jen now wants a much less formal and less publi­cized ceremony,” said the source. “And she believes Nancy’s loose lips are a threat to her privacy.”