If you have decided that you no longer need a Facebook account, follow the steps below to delete it. 
Sign into Facebook
visit www.facebook.com and sign into Facebook with your username and password.
Go to Settings Page
- Click on the gear button in the top right corner of the page, and click on “Settings” in the drop-down list.
Go to Security Settings
- In the top left corner is the menu list, click “Security” to go to the “Security” page.
Click Deactivation link
- Click “Deactivate your account” which is located in the bottom of the page.
- Select the reason of deactivation and click on the button. 
- Enter your password and click “Deactivate Now” button.