A Gwen Stefani fan is tracking her every move, lying in wait outside her parents' house, and leaving creepy letters and gifts for her ... according to a restraining order filed by Gwen's dad. 

Dennis Stefani filed docs requesting protection from a man named Richard Portnoy -- who Dennis says has popped up outside his home and Gwen's home 3 times -- twice in February and once last week. 

Dennis says he and his wife are terrified Portnoy will show up at their house again ... especially after one bizarre run-in. He says Portnoy made face-to-face contact with him at his house and read a letter to him about his feelings for Gwen. 

Even creepier, Gwen's dad says A Gwen Stefani fan is tracking her every move, lying in wait outside her parents' house, and leaving creepy letters and gifts for her ... according to a restraining order filed by Gwen's dad. 

Dennis Stefani filed docs requesting protection from a man named Richard Portnoy -- who Dennis says has popped up outside his home and Gwen's home 3 times -- twice in February and once last week.

Read more: http://www.tmz.com/2015/03/27/gwen-stefani-restraining-order-obsessed-fan-gavin-rossdale/#ixzz3VbJlchgG