Police guards have been removed from his residence where a large number of supporters gathered to celebrate the end of his house arrest.
His social media spokesman announced in a tweet that Hafiz Saeed is a free man.
Saeed has been declared a global terrorist by the United Nations and the US for his role in the Mumbai attack which claimed the lives of 166 people and maimed over 300 others.
He has a USD 10 million bounty on his head.
A judicial body of Pakistan had rejected a request from the government of Punjab to extend his detention by three months.
The LeT chief had been produced before the review board by Pakistan's Punjab government on Tuesday.
According to reports, a government official told the board there were enough evidences against Saeed to justify his detention.
The review board had earlier allowed a 30-day extension to Saeed's detention, which is set to expire in the last week of this month.