The 30-year-old Kiwi actress, who won an Oscar for The Piano in 1994 aged 11, gave birth to the twins prematurely.
"We can confirm that Anna Paquin and Stephen Moyer recently welcomed their twins into the world,” the pair's rep told People magazine.
"The babies were born a few weeks early, but are in good health and both Mom and Dad are overjoyed."
The bubs, whose names and sexes have not been disclosed yet, are the first for the couple, who married in 2010.
Stephen, 42, has two children (Billy, 12, and Lilac, 10) from previous relationships.
Season five of the hit HBO vampire drama True Blood finished airing late last month.
Anna and Stephen, who play on-and-off lovers Sookie Stackhouse and vampire Bill Compton on screen, announced the pregnancy in April, but didn't give a due date.
Their co-star Todd Lowe, who plays Terry Bellefleur, let slip to Celebuzz in June that Anna would be due "right before we start (filming) the sixth season."
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