"This is a significant moment of transformation for women in academia and leadership positions, both in our society and across the world," said Phakeng.
"We are delighted that the UCT council has placed its confidence in the experience and expertise of each of my executive colleagues."
Phakeng was Harrison's predecessor until she took over from Max Price in July 2018,
Harrison is a former deputy dean of research and postgraduate studies in UCT's faculty of engineering and the built environment.
Lange began her term of office in February 2018. She joined UCT from the University of Free State, where she held the same position.
Feris, the former director of the Institute for Marine and Environmental Law in UCT's law faculty, began her present role in January 2017.