Raif Badawi, who started the Free Saudi Liberals website to discuss the role of religion in Saudi Arabia, was arrested in June, Human Rights Watch said.
Badawi had initially been charged with the less serious offence of insulting Islam through electronic channels, but at a December 17 hearing a judge referred him to a more senior court and recommended he be tried for apostasy, the monitoring group said.
Apostasy, the act of changing religious affiliation, carries an automatic death sentence in Saudi Arabia, along with crimes including blasphemy.
Badawi’s website included articles that were critical of senior religious figures, the monitoring group said.
A spokesman for Saudi Arabia’s Justice Ministry was not available to comment.
The world’s top oil exporter follows the strict Wahhabi school of Islam and applies Islamic law, or Sharia.
Judges base their decisions on their own interpretation of religious law rather than on a written legal code or on precedent.
King Abdullah Bin Abdul Aziz, Saudi Arabia’s ruler, has pushed for reforms to the legal system, including improved training for judges and the introduction of precedent to standardise verdicts and make courts more transparent.
However, Saudi lawyers say that conservatives in the Justice Ministry and the judiciary have resisted implementing many of the changes that he announced in 2007.