Bristol Palin -- My Crazed Stalker's Back in Alaska!

It looks like Bristol Palin is about to get a proposal she doesn't want ... the stalker who once sent her an engagement ring is back in her home state of Alaska.

Palin filed legal docs against a Texas man who once showed up 2 years ago on Sarah Palin's doorstep during a birthday party for Bristol's son Tripp.

It was so alarming ... Bristol got a restraining order ... but it expired earlier this year.

The stalker returned to Alaska last week ... probably not for the wildlife.

We're told authorities contacted Bristol to let her know he was back in town -- and she made a beeline to the courthouse for another restraining order to protect Tripp and her.