You can delete an account either using SQL statements or on the RDS console based on your instance type.

Delete an account on the RDS console

Currently, the RDS console allows you to delete accounts for SQL Server 2008 R2 and MySQL 5.5/5.6 instances.

If master accounts are created for MySQL 5.5 and 5.6 instances, all other common accounts can be deleted only using SQL statements.
  1. Log on to the RDS console.
  2. Select the region where the target instance is located.
  3. Click the ID of the instance to visit the Basic Information page.
  4. In the left-side navigation pane, select Accounts to go to the Accounts page.
  5. Find the account you want to delete and click Delete in its Action column.
  6. In the displayed dialog box, click OK.

Delete an account using SQL statements

Currently, you can use SQL statements to delete accounts for MySQL 5.7, PostgreSQL, SQL Server 2012, and PPAS instances.

The initial or master account cannot be deleted.
  1. Log on to the RDS instance. For more information, see How to connect to ApsaraDB?
  2. Run the following command to delete the account.
    DROP USER 'username'@'localhost';