Perrette shared the happy news with fans on her Twitter account, revealing that Arklie, a marine, recently popped the question.
The actress tweeted: "Me and my Marine are totally engaged now…"
Perrette also vowed that she and Arklie will not officially tie the knot until California's gay marriage ban is overturned.
She has played Abby Sciuto in NCIS for nine seasons. The character has also appeared in NCIS's sister series JAG and NCIS: Los Angeles.
Perrette was previous married to actor Coyote Shivers for four years, but the couple split in 2004.
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