Guillermo Farinas was arrested for the third time in 48 hours on Friday, his family told the German Press Agency dpa.
"They brought him home at 10 am and then arrested him again at 3 pm," his mother Alicia Hernandez said by telephone from her home in Santa Clara, 280 kilometres from Havana.
She said the police arrested Farinas and 20 other opposition activists in the street on their way to a lay a wreath at a memorial to national hero Jose Marti.
"They only went two or three blocks. Then the police took them away and we are trying to find out which police station they are in," she said.
Farinas was also arrested on Thursday, for the second day in a row.
He was released Friday, fellow dissident Rafael Perez told the German Press Agency dpa on the phone from Farinas' home. Perez said no charges had been levelled against the prominent opposition activist.
Farinas' mother, Alicia Hernandez, had told dpa late Thursday that he was arrested in the afternoon along with a score of other opposition activists. The group had been meaning to inquire after three other dissidents who had been arrested that morning, Hernandez said.
"That was when they caught him. There was physical violence, and they led them in different vehicles to different police facilities," she said.
A day earlier, Farinas, 49, had been detained for six hours for taking part in a protest in Santa Clara. Farinas told dpa that he was held at a police station with 25 other people late Wednesday. He was later released without charge.
He said he and others had been protesting against the eviction of a pregnant woman and her two sons who had occupied an abandoned medical centre in Farinas's home town of Santa Clara.
In a telephone conversation with dpa, Hernandez said she had sent her son medication he needs to treat his epilepsy and coagulation problems.
Farinas, a trained psychologist who is part of a network of self- declared independent journalists in Cuba, was awarded the European Parliament's prestigious Sakharov Prize for Freedom of Thought in December. But he was not allowed to travel to Strasbourg to collect it.
Farinas has carried out 22 hunger strikes that have damaged his health. The latest of these ended in July, after more than 130 days, as Havana announced the release of 52 political prisoners following mediation by the Catholic Church.
The Cuban authorities say Farinas is a common criminal serving the interests of the United States. According to them, he was in jail 1995 and in 2002 for assault, although Farinas himself denies this and insists that he was in both cases the victim of violence.