I guess I don't really have very many fears, but the few I do have are kinda big for me.
#1: Stairs. Not stairs themselves, falling down stairs. I remember somebody falling down a staircase and dying at some point when I was really young, so yeah. Gods, the escalators at Universal Studios are a nightmare for me!
#2: Fire. I don't like fire. At all. So much that I don't even light candles and really dislike it when someone else lights a bunch of candles whenever I'm around.
#3: Losing someone to violence. The first two are, at least, mostly within my realm of control, but having someone I care about being taken away from me in a cruel way, having someone I love experience pain or the hatred of another in their last moments - that's something I just can't accept, and knowing that two people I care for are in even more danger of that than normal, everyday, gets to me.