The Spaniard has not played since he was injured playing for Arsenal on 19 October 2016 and will be with the Spanish club for pre-season.
But the 33-year-old is now hoping to get his career back on track after returning to his old club following his release by the Gunners.
Cazorla will be back with the Yellow Submarine from July 1 - no playing contract for next season has yet been offered, with the midfielder being given the chance to prove his fitness.
They wrote: "Today we have a very special thing to tell you because it is time to see someone very loved by the groguets... welcome back Santi Cazorla."
A statement on the website later read: "Cazorla returns home. The player will do pre-season with Villarreal's first team with the aim of recovering from the Achilles tendon operation in his right leg."