How to Delete a Battle.net Account
Blizzard Entertainment's Battle.net system links all of your Blizzard games through a single account. It's free to sign up for a Battle.net account, and your account keeps a record of your online game purchases and CD keys. You use the same Battle.net email and password when you log in to play Blizzard games online. If you'd like to delete your Battle.net account, you have to contact Blizzard customer services; you can't disable the account on your own. You can contact Blizzard in several ways.
Compose an email from the email address account you use to sign in to your Battle.net account. Explain that you'd like to permanently delete your Battle.net account. Write "Delete Battle.net account" in the subject line. Send the email to firstname.lastname@example.org.
File a ticket through Blizzard's Battle.net online support. Select "I have an issue with my account" in Step 1, then "I want to change something in my account" in Step 2. In Step 3, explain that you'd like to delete your account. Include your Battle.net email address in the message. Click "Submit."
Call Blizzard's account services department at 800-592-5499 to make your request by phone.