Here I will show you how to reset your Joomla admin password in a two ways. One is using phpMyAdmin and the other is using password reset script.
[*] Using a simple MySQL query with an application that manage your database.
[*] phpMyAdmin, almost available on all hosting.
[*] Login to your phpMyAdmin.
[*] Navigate to your Joomla database.
[*] Click “jos_users” table.
[*] Find an entry with name “Administrator” or username “admin”, click edit (the one with pencil pic).
[*] Make sure you are now on “jos_users” table(1).
[*] Make sure entry name is “Administrator”(2).
[*] Make sure the entry username is “admin”(3).
[*] Choose “MD5” from function column dropdown on “password” row(4).
[*] Enter the new admin password in the value column on “password” row(5).
[*] Hit “GO” to save.
[*] Using a script.
I found this Joomla administrator password reset script , it will reset your Joomla admin password.
All you have to do is upload the script to your Joomla installation and open the script from your web. Easy enough huh?