The men were brought from the main American base at Bagram and another US base in the southern city of Kandahar and released in the capital.
Col. James Yonts, the US military spokesman in Afghanistan, said the 53 were "low-level combatants" who committed hostile acts against civilians, Afghan forces and US-led coalition forces.
"These individuals were found no longer a threat to anyone," he told reporters in Kabul.
American forces have detained thousands of people since entering Afghanistan in 2001 to oust the former Taliban government and end the country's role as a haven and training ground for al-Qaida militants.
Most have been released, but many have spent long years in US jails in Afghanistan or at Guantanamo Bay, Cuba.
Sibghatullah Mujaddedi, head of Afghanistan's peace and reconciliation commission, told the released prisoners that although some of them may be innocent, they shouldn't complain, but instead be thankful to be free.
The release comes amid allegations that US military personnel at Bagram and at other detention facilities have abused prisoners. The US military has said it would not tolerate any maltreatment.
Four of those who were released and spoke to The Associated Press said they were not abused while in detention.
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"No one has beaten me during the last eight months and I haven't heard of anyone else being beaten," said Mohammed Anwar Hanifi, 38, who worked as a government official in eastern Paktika province before being arrested last October. "I was interrogated a lot, but they found no proof I was guilty. It is why they released me."
It was not immediately clear how many Afghans are still in US military detention. A month ago, 85 other prisoners were released.
There was no apology for the 53, but officials handed each of them 10,000 Afghanis (US$234), and a new turban as well as a letter from the US military confirming their release.
