A 21-year-old man was arrested at the singer's $3 million mansion in Calabasas, California, which she bought last week, and charged for burglary and trespassing.
A source told gossip website TMZ.com that the brunette beauty, 21, and a friend called the police because they heard a strange noise shortly after they arrived at the five-bedroom property.
A man then rang the front doorbell and asked if the 'Spring Breakers' actress was at home, but her friend insisted she wasn't and he left.
Law enforcement sources said that when officers from the Malibu/Lost Hills department arrived a short time later, they found the man had broken into the star's guesthouse.
He was arrested and is currently being held on $50,000 bail.
Selena has had a number of issues with intruders in the past.
Juan Garcia, who was arrested outside the 'Come & Get It' hitmaker's old house in Tarzana, California on January 25, was recently sentenced to 120 days in Los Angeles County Jail for trespassing.
The singer also had a terrifying encounter with a stalker a few years ago.
Thomas Brodnicki, 46, was ordered to stay away from the singer and actress in 2011 after repeatedly talking about killing her while under psychiatric hold.
He later admitted the former Disney star needed to be protected from him.