Delete your Facebook account

Log into your Facebook account and click on "Account -> Account Settings" link given in the right corner.

It'll open Settings page. Click on "deactivate" link under "Deactivate Account" section.

OR you can directly click on following link to deactivate your Facebook account:

Deactivate Facebook Account

Select any desired option in "Why are you deactivating:" section and click on "Deactivate My Account" button.

PS: Above procedure will only deactivate your account. If you want to permanently delete your Facebook account, use following link instead:

Delete Facebook Account Permanently