The 38-year-old, seen in TV shows such as "How I Met Your Mother", says that a man named John Hobbs, who is mentally unstable, is threatening to kill her through posts on Facebook, MySpace and her website, reports

Alyson Hannigan
Alyson Hannigan. Pic/Santa Banta

Hannigan also claims that Hobbs threatened to rape her by writing online: "Lets see How can I get myself in trouble today. If I go with what I've been accused of most of my life, I suppose I should start with being a rapist, so any nice girls out there want to get raped."

The actress has demanded protection for husband Alexis Denis and daughters Satyana, three and nine-month-old Keeva.  A hearing has been set for March 6 when a judge will decide whether to make the restraining order permanent.