Dar, who was the chairman of the Legislative Council in 2006, was welcomed to PDP by party patron Mufti Mohammad Sayeed.
Sayeed said it was time that all right thinking people, whether in the NC or elsewhere, join hands with him in order to retrieve the state from "uncertainty and misgovernance".
He said there were a large number of workers and activists in the NC with genuine concern for the resolution of Kashmir issue.
"Unfortunately, they have been let down time and again by their leadership. The PDP doors are open for anybody who wants to play an active role for restoration of state's dignity and empowerment of its people," he said.