Keanu Reeves Gets Protection From Alleged Stalker Who Thinks They're Related

Keanu Reeves is getting protection from a man he claims showed up at his home, apparently hell-bent on trying to prove they're somehow related.

The "Matrix" star's lawyer, Mathew Rosengart, beelined it to court Tuesday asking the judge for a temporary restraining order ... to protect Keanu and his partner, Alexandra Grant, from a 38-year-old man named Bryan Dixon -- who he claims is transient and has been harassing them for months.

According to new legal docs obtained by TMZ, Keanu hired a security firm to investigate Dixon after claiming he kept showing up at the actor's home uninvited, and finding different ways onto the property.

The docs say Dixon trespassed 6 times from November through January -- the first time, on November 5, he entered through a side gate and fell asleep in the backyard before getting the boot.

Dixon allegedly came back the next morning and left a "suspicious and alarming" backpack on Keanu's property, which they say included a DNA testing kit “apparently intended to use on Mr. Reeves in a delusional attempt to prove they are blood-related."

Keanu's legal team says Dixon is a complete stranger to the actor, but they've discovered some red flags -- for instance, Dixon currently has a bench warrant issued against him in Rhode Island for alleged breaking and entering with felonious intent, possessing burglary tools and vandalism.

Keanu’s lawyers claim the guy's rap sheet goes back 2 decades.

What's more, Keanu's camp claims Dixon keeps posting disturbing messages on social media referring to himself as "Jasper Keith Reeves" and has set out to assign all of his personal "rights" to Keanu and put Keanu in "charge" of him.

The judge granted a temporary restraining order barring Dixon from coming within 100 yards of Keanu and Alexandra.