Kyiv Appeals Court Judge Iryna Grygoryeva announced the decision after one of the defendants -- former Interior Ministry officer Mykola Protasov -- reportedly felt faint in the courtroom. Protasov and his two co-defendants -- Valeriy Kostenko and Oleksandr Popovych -- face murder charges.
Relatives of the slain journalist and their lawyers said they were "surprised" by the court's decision to adjourn the trial for so long.
Gongadze's mother Lesya has refused to attend the hearings, saying she no longer has faith in Ukrainian justice. At an earlier court session in December, the judicial panel turned down her request to have an additional probe help find those who orchestrated her son's killing.
Gongadze's widow Myroslava, who now lives in the United States, is attending the proceedings. Addressing reporters outside the courtroom, she said those truly responsible for her husband's killing are still on the loose.
"The next step will be when the organizers of this crime will be brought to justice," she said. "They are known, and they must be punished as well as the people sitting in the dock today."
A prime suspect in the case, former Interior Ministry General Oleksiy Pukach, is still at large. Many in Ukraine suspect then President Leonid Kuchma of ordering the assassination. Kuchma denies the accusations.
Audio recordings secretly made in Kuchma's office by a former bodyguard, Mykola Melnychenko, contain a passage in which a voice that is reportedly Kuchma's suggests that Gongadze be "removed and thrown to the Chechens."
(UNIAN/"Ukrayinska pravda"/ForUm)