"The strike aims to push for an urgent court hearing to release those lawyers in prison," Magdy Abdel Halim told state-run Ahram Online website.
Last week, a court in the southern governorate of Minya sentenced seven lawyers to five years in prison and one lawyer to three years.
The lawyers were charged with blocking access to a public facility, preventing a judge from carrying out his duty, and insulting the judiciary in a case that dates back to the defendants' protest outside a local court in March 2013.
The 2013 protest came after what the syndicate says was a judge's handing down of a harsh sentence to some of the lawyers' clients without hearing the defence.
Abdel Halim said that the nationwide strike "sends a strong message that lawyers are united against the harsh verdict given to their Minya colleagues", according to Ahram Online.
Despite Saturday's strike being held for one day, the strike in Minya – which first started when the lawyers were sentenced – will continue "even if the jailed lawyers are released", according to Abdel Halim.
"We are protesting for justice," he said, adding that lawyers who did not comply with the strike would be referred to the Syndicate’s disciplinary committee.
In response, MP Mohamed al-Aqqad issued a statement urging the Syndicate to suspend the strike in order not to affect the "citizens' interests".
"Citizens are the only ones affected by the crisis, which must be resolved promptly," he said.
Aqqad also urged an urgent meeting between the Syndicate chief and the justice minister, to be attended by the Prime Minister and Parliament Speaker.