'Teen Mom' Star Jenelle Evans -- Arrested ... Again

"Teen Mom" star Jenelle Evans has just been arrested ... for the second time in a week, TMZ has learned.

A rep for the Brunswick County Sheriff's Office tells TMZ, she was arrested moments ago in North Carolina for violating a domestic violence protective order. She is still in custody.

Details surrounding the arrest are unclear -- though as we previously reported, Jenelle was busted just last week for allegedly making harassing phone calls and threatening her ex-roommate.

Jenelle's still on probation for beating up some chick in a nasty street fight last year -- so this arrest could mean even more serious trouble.