The 23 year old motorbike racer from Wyken in Coventry, finished fourth in Portimao in the final round of the Championship which was enough to give him the title.
Speaking to the CT, Crutchlow said: "To come from the back streets of Coventry to world champion is pretty special. "It's been a tough season and all credit to Yamaha who have done a fantastic job."
Cal will step up to World Superbikes next year.