If you want to change the WordPress dashboard login logo then this piece of code can meet your requirement.
Just paste this code in the your theme functions.php
[php]
function custom_login_logo() {
echo ‘<style type="text/css">
h1 a { background-image:url(‘.get_bloginfo(‘template_directory’).’/images/custom-login-logo.png) !important; }
</style>’;
}
add_action(‘login_head’, ‘custom_login_logo’);
[/php]