Katy Perry is seeking court-ordered protection from a homeless man she claims keeps showing up to her home uninvited … and her security team believes the guy won’t take “no” for an answer.

According to new legal docs, obtained by TMZ, Katy filed a temporary restraining order against a 43-year-old man named Ross Elliott Hedrick. She says he’s a transient and has twice visited her property in Santa Barbara, California.

Katy filed the TRO on June 18 … and in her request, she also seeks protection for Orlando Bloom, noting he is her “partner” who lives with her. As we first reported, Katy and Orlando have since split.

The “Last Friday Night” singer claims Hedrick visited her Santa Barbara estate multiple times in May … she says he was arrested after the first unwanted visit and then returned a week later.

Katy’s security services company says Hedrick appeared to have an aerosol can and a butane lighter the first time he dropped by … and they say on his second visit, he tossed a blanket over the security gate.

The company says Katy’s fears about the threat posed by Hedrick have merit, and there’s a high likelihood the guy will keep trying to contact her. They also included some screenshots of Ring video, which they say show Hedrick on her property.