The 29-year-old Brazilian provides a welcome boost to the strikeforce while Raul Jimenez is on the sidelines and will spend the rest of the season at Molineux, subject to work permit and international clearance.
Wolves will then have the option to buy him for around £22million in the summer.
Jose has been with Sociedad since 2016 and scored 62 times in 170 appearances for the La Liga outfit.
He got both of their goals in a Copa Del Rey win at Cordoba last Wednesday.
The former Brazil Under-20 international is yet to travel to England, though, and not expected to be involved at Chelsea this coming Wednesday as new Brexit rules have delayed the process slightly. He will wear the No.12 shirt for Wolves.