integrating codeIgniter with wordpress

Hi , 
I am new to CodeIgniter or I can say I have a little knowledge. My client want to integrate his previously existing CodeIgniter site with new wordpress site. Is there any tutorial about that then please share the link.

There are no tutorials for this, as it can mean a whole bunch of things. You need to specify what have been built with CodeIgniter and what part you want to integrate with Wordpress.

Both of them are made in PHP, and are of course doable. But it will require quite some skill depending on what type of integration are needed.