Sheryl Crow is in fear for her life ... claiming a delusional fan believes she stole money from him ... and now he's threatening to shoot her ... this according to legal docs obtained by TMZ.
Crow just filed a request for a restraining order against 45-year-old Phillip Gordon Sparks -- a fan who allegedly began posting "disturbing" messages about the singer on Facebook back in April.
In the papers, Crow says, "It was clear to me that [Sparks] was deeply disturbed because his posts were delusional, rambling, filled with profanity and laced with angry rants."
Crow says Sparks claimed in one of his posts that she "had broken into his house because I was looking for his gun."
"Other posts claimed that I was supposedly filming him surreptitiously, tried to have him arrested and that I had stolen money from him."
Crow notes, "All of these allegations were, of course, categorically false."
But Crow says Sparks took things to a scarier level last week ... claiming he went to the offices of the Screen Actors Guild and told an employee that he was going to "just shoot me."
Crow says the news was "extremely alarming" ... and she now fears for the safety of her family, employees and her manager ... whom Sparks allegedly mentioned by name in one of his posts.
Crow is asking for protection for herself and 16 other people -- including her two sons, nanny, sister, assistant, parents, siblings and managers.
A judge has yet to rule on Crow's request.