The Herald newspaper said Mugabe, 93, and his wife Grace gave Junior Gumbochuma the money at her birthday celebrations, while the couple's children gave her USD 10,000.
"The gift was to thank Mrs Gumbochuma, a pastor, for the pivotal role she played in raising the First Family's children," the newspaper said.
Gumbochuma, who is Grace Mugabe's elder sister, celebrated her 60th birthday yesterday as Grace celebrated her 52nd at one of the Mugabes' farms in Shamva, northeast of Harare.
Zimbabwe's public salary wage bill uses up 91 per cent of total revenue and the economy has halved in size since 2000.