The deal is believed to be worth 9 million.
"Stefan De Vrij will arrive tonight at Fiumicino airport and tomorrow morning at 8am will undergo his medical at the Paideia clinic," announced Lazio director of communications Stefano De Martino.
"We welcome with joy the best defender at the World Cup. He is an international-level signing."
For the big stories and the banter follow us on Twitter: @tribalfootball