According to facebook:
If I reject a friend request, will they find out?
No. When you reject someone, their friend request will leave your list of friendships to confirm, but they will not be notified.
However, I have found a way to find out if someone has rejected you or not.
- Login to facebook, and click on “privacy” on the upper right corner.
- Click on “poke, message, and friend request settings”
- Then on the lower right corner, you should see a “People who can see your profile”
- The people listed there are the ones that you have added, but have not accept or reject you.
So, if you have requested to be added on someone’s friend list, but always get a “friend requested” on the status page, but the name isn’t listed from the “Poke, message, and friend request settings” page, then you have been denied.