The tribunal, which is separate to a police investigation, will recommend whether Gula-Ndebele should remain in office.
Gula-Ndebele is charged with corrupt conduct. If convicted, he faces a maximum of 15 years in jail and a fine.
Police accuse him of promising James Mushore, a former director of National Merchant Bank (NMB), that he would not be arrested if he returned to Zimbabwe.
Mushore fled to Britain in 2004 at the height of a Zimbabwean banking crisis that saw several finance houses shut down by the country's central bank.
The former banker, who was arrested upon returning to Zimbabwe in October, has been on the police wanted list for siphoning foreign currency from the country to offshore accounts.
Media reports say the allegations against Gula–Ndebele are politically motivated and a direct result of his clashes with Patrick Chinamasa, the justice minister, over control of the attorney-general's department.
Mugabe's government has previously vowed to tackle misconduct, especially by senior officials, but analysts say an anti-corruption commission appointed in 2006 was ineffective and barely functional.