The independent Human Rights Asscoaition called for the "release of all those arrested during the events on March 11 without delay and without pressing charges against them."
Media reported Saturday that security forces arrested dozens of stateless Arabs, locally known as bidoons, during and after the protest.
The rights association also accused security forces of using excessive force in dispersing the protest and using tear gas canisters inside people's homes.
About 500 demonstrators took to the streets in Jahra, west of Kuwait City, immediately after Muslim prayers Friday, while hundreds protested in two other locations.
Stateless Arabs, estimated at more than 100,000, protested last month for three consecutive days until officials gave them assurances their grievances would be addressed.
But parliament refused on Tuesday to debate a bill that would give them civil rights because the government, backed by many MPs, said it prefered to issue executive decisions granting those rights rather than a law.
The rights association said the government and parliament should immediately adopt legislation granting the undocumented people their basic rights.
Kuwait launched a crackdown on the bidoons in 2000, depriving them of health care, education and jobs.