The 68-year-old Rousseff has been suspended from office for 180 days, pending her trial. Vice-President Michel Temer is expected to assume the presidency during that period and name his cabinet shortly.
"I never received bribes, I have not engaged in money laundering. There are no grounds for impeachment," Rousseff said in a televised statement.
"I wish to clarify this again after the Senate's decision and point to the risks of fraudulent impeachment, which is a coup," she said.
Brazil’s president has been facing a wave of public discontent for over a year amid the country’s struggling economy and a major corruption scandal in the state-owned Petrobras petroleum company.