Facebook allows users to connect through relationships called friendships. Clicking the "Add as Friend" button on a user's profile page sends a friendship request to that user. From there, the user may choose to accept or deny the request. If you've sent out a request by mistake or are having second thoughts about a request, you can easily cancel the friend request.
Cancel Request You've Made
If you wish to cancel a pending friend request that you have sent to someone, you can do so by visiting his or her profile page. Once on the profile page, navigate to the left column, below the person's profile picture. Click the link that says "Cancel Friend Request." Once you do so, the link will change to gray letters letting you know that the friend request has been canceled. Your pending friend request is then removed from the other person's request list.
Cancel Requests From Others
If you've received a friend request from someone else that you wish to cancel, you can do so from your requests screen by clicking "Not Now" next to the person's request. Doing this removes the request from your profile, but does not notify the sender that you have denied the request.
Checking Pending Requests
You can check on pending requests by visiting the profile of anyone you've sent requests to. If you've sent a friend request and the "Add as Friend" link appears, there is no pending friend request. This means the user has denied the friend request you sent. If "Awaiting friend confirmation" appears, the user has neither confirmed nor denied your pending friend request.
Unable to Send Request
If you navigate to a user's profile page and are unable to locate the link to send a friend request, the user has blocked the friend request feature through his Facebook privacy settings. If you wish to do the same, click on "Privacy Settings" from the "Account" drop-down menu within your account. Click "View Settings" in the "Connecting of Facebook" section. Select your setting next to the "Send you friend requests" menu.