Kris Jenner has obtained a court order to keep a former security guard away from her, after he was busted trying to contact her at her home ... for the 3rd time.

Kris' attorney, Shawn Holley, filed a request for a restraining order Wednesday, detailing Joshua Jacobs' latest attempt, on May 1, to get face-to-face with the Kardashian matriarch. In the docs, Kris says Jacobs... "crashed his vehicle through the gate to our community, came on to my property looking for me at around 1:00 AM."

Jacobs was actually kneeling down in front of the security keypad on her house, and pressing keys when Kris' personal security spotted him. He was charged with felony stalking, and arraigned Wednesday.

According to docs, Jacobs made the same mad dash for Jenner's house 2 weeks earlier, and also showed up in March ... with his grandmother in his car.

The restraining order was granted, and Jacobs has been ordered not to harass or contact Kris ... and must stay 100 yards away from her.