can anyone recommend me a really scary horror movie?

Martyrs (Laugier, 2008) - it's a horror film that completely over-steps the line. It's French and contains some of the strangest, sickest and most shocking elements I've seen.

Itchi the Killer (Miike, 2001) - a Japanese exploitation movie featuring as much gore and shock-inducing violence as the crew could muster.

Mum & Dad (Shiel, 2008) - less gorey, but more strange and sick. I'm not quite sure how to explain.

Dogtooth (Lanthimos, 2009) - more deeply upsetting than gorey, and was even condemned by the Prime Minister of Greece (it's a Greek film) when it was first released.

A Serbian Film (Spasojevic, 2010) - you probably heard about the controversial release and cuts of it, and it's just freaky - pure exploitation cinema.

Audition, Hellrasier, Evil Dead 1 and 2, Imprint, Videodrome, The Fly

I spit on your grave, Paranormal Activity 1 & 2, The Evil Dead Triolgy, Omen, American Werewolf in London, The Orphanage, Cannibal Holocaust,

Hostel

House Of wax

Dead Silence

Jeepers Creepers

Children Of the Corn

Shutter

Last House Of the Left

Devil

The Orphan

Well many of the ones you've listed are pretty scary and are well-known as good horror films. What is widely known as up there as one of the scariest movies of all time, or one of the best, is The Shining by Stanley Kubrick. If you haven't seen it, you should. It's a trip! LOL

Classic: IT Part 1 and 2 :) Its not a horror blood and gore movie persay but its beautiful when it comes to the art of scary. Its what sparked my craving for terrifying movies. That or watch The Last House on the Left. THAT movie is a good one. ;)

Lol you've seen like all of them. Ok let's see um..

-Paranormal Activity

-Paranormal Activity 2

-Human Centipede

-The Hitcher

-The Craft

-The Skeleton Key

-House of Wax is a really good one

i was terrified when i was watching "audition" and "martyrs".probably because they are really disturbing, shocking and horrifying at the same time.and not just like a movie that we watch and it ends.they are messing with your mind.after watching either of them i was like

"why did i thought after i watch this movie nothing would change and i would still enjoy the horror genre instead of being REALLY scared by it?" or "damn me! why did i thought watching this would be so enjoyable?" or even "goddamn you, people! why do you recommend these movies to other people"

but beside that i think they are well made scary movies that aren't just for fun.i would also recommend "may".

Shaun of the Dead? haha I love that movie.

Ummm I heard that Case 39 was scary and good. Shutter Island was pretty good. Those two aren't gory, but thats all i got. Sry couldn't be more help.

The Amityville Horror