Centre-half De Wijs, 23, has agreed a three-year contract and is the Tigers' third signing in as many days.
'The 23-year-old centre-back has signed a three-year deal, with an additional one-year option held by the club,' the Tigers said in a statement.
'(He) becomes the Tigers' fourth signing so far this summer as he follows in the footsteps of Eric Lichaj, David Milinkovic and Reece Burke.'
De Wijs spent last season and half of the previous campaign on loan with Excelsior Rotterdam, making 34 appearances in the Eredivisie.
Hemade his senior debut for PSV in a Champions League tie against Wolfsburg in 2015 and made a total of four appearances for the club.
'This is a big step for me and I'm happy to be a Hull City player,' De Wijs said.
'Playing in England has always been one of my ambitions and this is the right time for me to make this step. I am really excited to be here and I want to give everything for this team.'
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