Zayd Saidov denies the fraud, rape and other charges against him, and the opposition in the ex-Soviet Central Asian nation has denounced the case as political persecution.
Saidov, a businessman who previously served as industry minister, was arrested in May, a month after he announced the creation of a political party to challenge President Emomali Rakhmon.
Rakhmon extended his more than 20-year rule in November's election that was criticized by Western observers for lack of real competition.