Issawi’s sister, Shireen, posted a message on Facebook reading "Samer Issawi is free."
She also posted a photo of her 34-year-old brother smiling and flashing a V sign from inside an ambulance.
"Samer Issawi's family was ordered by Israeli terror police earlier today not to celebrate and to take down the flags raised at their home," according to The Free Samer Issawi Campaign page on Facebook.
Samer Issawi became a national symbol in the Palestinian struggle against Israeli oppression after launching a hunger strike last year to protest his imprisonment.
He ended his nearly-nine-month strike on April 23, 2013 after striking a deal with Israel's prison authorities to serve an eight-month sentence for an alleged parole violation.
Thousands of Palestinians had taken to the streets on an almost daily-basis earlier this year to demand Issawi's release. They frequently confronted Israeli occupation forces who fired tear gas, rubber-coated bullets and live ammunition at them on multiple occasions.
The movement to release Issawi and other Palestinian prisoners quickly gained steam, drawing an avalanche of international support, with solidarity protests being held in Europe and the United States.
Issawi was first arrested about 11 years ago for arms possession and released in a Hamas-Israel prisoner exchange deal in October 2011.
However, Issawi was rearrested in July 2012 under Israel’s so-called administrative detention law.
The law, which has been in place since the end of the British mandate in Palestine in 1948, allows for the arrest of Palestinians if they are deemed a "threat" to the Zionist regime's national security.
Palestinian hunger strikes have posed a new challenge to the Israeli regime, which has come under international criticism for its practice of detaining prisoners without trial.