Bernie Salazar Ortiz, aka Bernard Adelmo Ortiz, was sentenced to probation after pleading guilty to stalking the star in 1998, but violated the terms by trying to contact Ronstadt through her family and wound up spending three years in prison, TMZ.com reported.
After his release in 2000, he was arrested again at a Ronstadt concert.
The protective order granted Monday said Ortiz was due to be released from jail this week and Ronstadt was frightened for her safety.
Ortiz has a history of mental illness, the court documents say.
The protective order says Ortiz may not go 1,000 feet within Ronstadt or any one in her family, nor try to contact any of them by phone or letter or attend any of her concerts.