Heads of state from more than 40 countries attended the inauguration and Mr Ramaphosa thanked them for their “sacrifices and tireless contributions” for the “liberation of our land”.
He paid tribute to Nelson Mandela and said that in the 25 years since Mr Mandela was inaugurated as South Africa’s first democratically elected president the country had “known both seasons of plenty and times of scarcity”.
Many South Africans still go to bed hungry, many succumb to diseases that can be treated, many live lives of intolerable deprivation,” he acknowledged.
“Too many of our people do not work, especially the youth,” he said speaking on the 27% of young people who are unemployed.
He said the challenges the country faced were “real” but “not insurmountable” and “can be solved”.
Mr Ramaphosa is expected to choose his cabinet within the next few days, a challenge in itself in a party with many factions.
“He will be judged on a very high bar and the next step is the cabinet,” Daniel Silke, director of the Political Futures Consultancy, told Reuters.
“If it contains any semblance of the dead wood from the past he will be severely critiqued,” he added.
Mr Zuma did not make an appearance at the inauguration, having attended court in the city of Pietermaritzburg on Friday in relation to corruption charges.
He told supporters he did not have time as he was “fighting to stay out of jail”.