The young talent, who has been compared to Manchester United great Nemanja Vidic and Chelsea hero Branislav Ivanovic as a top defensive prospect, signed from Serbian side FK Jedinstvo Ub.
The 19-year-old can play in midfield and across the backline, but knows he needs game time in Europe to continue growing.
"For my development, I mainly have to train and play minutes at the highest level," Pivas said. "Willem II is known for giving young players a chance. I hope that I can gain experience here and then take it with me to my higher goal, playing in the Premier League.
Willem II technical director Tom Caluwé added: "We have good contacts in England and Miodrag came into the picture at our scouting.
“He is a very talented defender who wants to gain experience at the highest level. We can help him with that and it gives our selection a quality boost across the board."