According to a government notice, those who are facing life sentences and who have served at least 20 years of that sentence could be released.
Some 1,500 prisoners were released in March but prisons remain overcrowded, with a total of 20,000 inmates against a capacity of 17,000.
The amnesty frees all female prisoners save those convicted for violent crimes. All juveniles and the terminally ill will also be released.
Men who have served at least a quarter of a three-year prison sentence will also be freed.
Zimbabwe has granted more than a dozen amnesties over the years to decongest prisons, but they remain overcrowded and squalid.
According to official figures coronavirus has been slow to spread in Zimbabwe, but there are fears the country’s health facilities will not be able to cope if numbers increase.