If you mean using something like Apache's .htaccess, that's a decent level of security. Be aware that relying on HTTP Authentication isn't as secure as an encrypted connection -- the username and password are sent out in HTTP Headers in plain text.

Anyone dedicated with sufficient time could sniff the appropriate packets. It's better than nothing, though, and it's not hard to use. (Hey, PerlMonks uses cookies to verify identity, which have the same problem. Not that vroom is storing compromising photos of EDC employees on kali or anything...)