Jessica Simpson's Book Tour Security Beefing Up After Anti-Fur Protests

Jessica Simpson will have extra venue security going forward on her book tour ... thanks to a bevy of anti-fur protesters who seem to be following her every move.

The "Open Book" author's already had events in NYC and L.A. interrupted by angry animal rights activists storming in and yelling. So, the upcoming venues on her tour are on notice ... and we're told they are being proactive about it.

At least 2 people who run venues Simpson will visit this week tell TMZ ... security will be beefed up in various ways in an attempt to keep protesters from striking again.

At one of the locations ... all guests entering will be subject to a search, in which security will be checking for all the normal red flags like weapons ... but will also be on the lookout for protest materials like signage or noisemakers.

We're told, as an added safety measure, all guests will have to have purchased a ticket and a copy of Jessica's book to be allowed entry.

We broke the story ... Simpson was being interviewed by Katherine Schwarzenegger at the Aratani Theatre in L.A. Monday night when anti-fur peeps popped in and made a scene, but Jessica laughed it off as they were escorted out.

Of course, just days earlier in New York ... Simpson's book signing at a Barnes & Noble was disrupted by protesters, and she got accosted by a couple more hours later as she was leaving a restaurant.

Jessica's worn fur in the past, but it's unclear if she still does or why the activists are so hellbent on making her the focus of their scorn and ridicule. One thing's for sure though ... she's not alone.