India-born Rajat Gupta had leaked boardroom secrets to Raj Rajaratnam, a former hedge fund manager who is serving 11 years in prison.
Gupta, 67, was released on Friday, the Press Trust of India said, quoting his record at Federal Bureau of Prisons.
The US court has agreed to re-hear his appeal against his 2012 conviction, reports say.
Gupta completed the last two months of his jail term at his home in Manhattan, after being released in January from a correctional facility.
He was confined to his apartment and was required to wear an ankle bracelet that monitored his movements, the Press Trust of India reports.
During the court case, which resulted in Gupta being found guilty in June 2012, the jury heard secret recordings of conversations between him and Rajaratnam.
The trial focused on a phone call made to Rajaratnam on 23 September 2008, minutes after Gupta had listened to a private conference call discussing a $5bn (Â£3.4bn) investment in Goldman Sachs by Warren Buffett's company Berkshire Hathaway.
The deal was due to be made public after stock markets closed that day.
According to phone records, Rajaratnam bought $40m in Goldman Sachs stock moments after the phone call, earning nearly $1m.
Apart from the two-year prison term, Gupta was also fined $5m.
Gupta, who was born in India and educated at Harvard, also served on the boards of Procter & Gamble, the Rockefeller Foundation and the Bill and Melinda Gates Foundation.
A former Goldman Sachs board member has been released after serving a two year sentence for insider trading in the US.