"Entourage" actress Alexis Dziena had screaming fits and threatened to hurt her boyfriend if he broke up with her ... so claims the fearful BF who just got a restraining order against her.
Jeffrey Francis Ausley says he and Dziena had been dating for a few months, but when he tried to end it, she went crazy ... screaming, throwing tantrums and threatening to harm Ausley and herself.
In court docs, Ausley says the final straw came when Dziena showed up at his house last week with a bag of clothes and announced she was moving in ... and if he didn't go along with it, she'd have him arrested "because she knew how."
Dziena -- who played E's psycho ex-GF on "Entourage" -- has now been ordered to stay 100 yards away from Ausley.
She's been down a similar path before ... in 2011 she tried to get restraining orders against her parents -- fearing her dad would murder her for her money -- but a judge turned her down.
We reached out to Dziena ... so far no word back.