"The people of Israel welcome the release of Jonathan Pollard," said Netanyahu, who had long pressed for the spy's release.
"As someone who raised Jonathan's case for years with successive American presidents, I had long hoped this day would come.
"After three long and difficult decades, Jonathan has been reunited with his family. May this Sabbath bring him much joy and peace that will continue in the years and decades ahead."
He was freed from prison in Butner, North Carolina, but a spokesman for his Israeli supporters group had no immediate word on Pollard's whereabouts after his release.
He is barred from leaving the United States for five years unless granted permission by President Barack Obama.