Schurrle was long linked with a switch to west London and discussed life in the capital with Mourinho at former Blue Michael Ballack's recent testimonial in Germany.
"I'm really looking forward to working with him (Mourinho)," Schurrle said.
"I got to know him at Michael Ballack's testimonial a few weeks ago where we talked a little bit.
"He gave me advice on where to live and also explained what he expects from me.
"He's a very good person with a big personality; he's a great manager so it's an absolute honour for me to now be one of his players."