You can hide your friend list on Facebook.To do this, At first click on Profile on the blue bar at the top of the screen.
Scroll down to the beginning of your Friends list and click on the pencil to the right of the word Friends.
After clicking the pencil option you will find a Tab.Click on the Change Visibility Settings Option.
Scroll down and click on the See your friend list box as shown as below.
Choose the Custom Privacy.Make this visible to Only me. Save Settings .That's it.