'State of disbelief'
Hamdan, who was the first man to appear before a US war crimes court since the end of World War Two, was transferred to Yemeni custody and taken to a state security prison after his arrival at a military base at Sanaa International Airport.
Navy Lieutenant Commander Brian Mizer, Hamdan's US military lawyer, said the Yemeni was "in a state of disbelief" on hearing news of his transfer home.
Mizer said he did not know what plans the Yemenis had in place for Hamdan's detention.
His family in Yemen had asked to meet him when he arrived but the government delined their request, a Yemeni official told news agency AP.
Hamdan, who has never seen his seven-year-old daughter, was taken to Guantanamo Bay in May 2002 after being picked up by US forces in Afghanistan.
He had been in Afghanistan since the mid-90s and was first hired by Osama bin Laden to work on his farms.
US prosecutors say he was then promoted to driver and also doubled as a bodyguard.
After the September 11, 2001, attacks on the US, prosecutors say Hamdan drove Bin Laden between various safehouses as US forces tried to pinpoint the al Qaeda leader's whereabouts.
US prosecutors said Hamdan should receive a custodial sentence of 30 years to life and had argued that the time he had served in Guantanamo should not be deducted from the overall prison term.
However, the military judge dismissed that argument saying Hamdam was just a "small player" in the al-Qaeda network.
Around 90 Yemenis are still being detained in Guantanamo, many of whom are expected to be released by the US military in the near future.
However, there are concerns among human rights groups that many former Guantanamo Bay detainees will not be able to return to their home states.