Busisiwe Mkhwebane's suspension came a day after she opened a probe into an alleged coverup by President Ramaphosa of a 2020 burglary at his farm.
"Advocate Mkhwebane will remain suspended until the... process in the National Assembly has been completed," the presidency said in a statement.
Ramaphosa's office also said Mkhwebane's deputy would take over all pending cases.
"The absence of Advocate Mkhwebane from office will therefore not impede the progress of any investigations that are pending or underway," its statement read.
Parliament, dominated by Ramaphosa's African National Congress, agreed last month to open impeachment proceedings against Mkhwebane.
For years she has filed, and lost, a series of cases against her impeachment.
Her appointment during the presidency of Jacob Zuma was widely seen as an attempt to protect him from corruption claims.
Mkhwebane's impeachment proceedings are the latest skirmish in a battle to undo the rampant corruption of the Zuma era.
But Ramaphosa's political opponents say the scandal surrounding missing money at his game farm revealed a money-laundering scheme by the wealthy president, claiming that thieves had found some $4 million in cash hidden in his furniture.
