How to cancel friend request on facebook?

[Joe]

via Iphone app, thanks

[Jack]

Well press on the person that you need to cancel and you can find it over there

[dan]

Go to the profile of the person you sent a request to and click the same tab you hit to start the friend request. An option to cancel it will come up.

[Evelyn Diana Mejia]

You go to the person you requested and where it says request sent (you click on it) and it should bring several options down and the last one I'm pretty sure is cancel request (:

[Abhishek]

Well its quite simple, Just do the same you did to send the request, and instead of a "send request" button , there will be a "Cancel request" Button.
To be specific, Open their profile , and you will find it there. Good LUck