The `Die Young` singer received the chilling package in the mail and although she tried to shrug it off she admits it did frighten her.
She told NME magazine: "What`s the weirdest thing I`ve ever been sent? A bloodyknife. One of my fans said if I wasn`t his then I would be no one`s and he would come and take me. I`m kind of scared he`s going to make me into a lamp."
Ke$ha, 25, does not shy away from the weirder side of life and claims she once drank from a real human heart during a live performance in Australia.
She explained: "Yeah, that was real too. I did it on stage in Sydney. I think I was hanging out with Alice Cooper too much. I was really inspired. There wasn`t any good reason behind it."
The singer`s management try and get her to tone down her behaviour when she gets too crazy, but she doesn`t see it as a big deal when she does things like urinating in the street.
The pop star - who releases her new album `Warrior` later this month - added: "I got into a lot of trouble with my management for tweeting a picture of me peeing, because I pee on everything. It`s not a big deal, it`s not like I was pooping."