Valencia said on Monday they had reached agreement to sign Portuguese international midfielder Goncalo Guedes, who spent last season on loan at the La Liga club.
The deal for the 21-year-old former Benfica player could be worth as much as 50 million euros ($58.4 million), according to reports.
Guedes joined PSG in January last year but failed to earn a place in the French champions' star-studded lineup.
His loan spell at Valencia was a success as he played 33 games and scored five goals, earning him a place in Portugal's World Cup squad in Russia.
Valencia tweeted a picture showing Guedes shaking hands with the club's Singaporean owner Peter Lim with the caption: "Do you recognise him? He's ready to come home!"