The dinosaur, named Mbiresaurus raathi, was only about 1 metre tall with a long tail, and weighed up to 30 kilograms, according to the international team of palaeontologists that made the discovery.
"It ran around on two legs and had a fairly small head," Christopher Griffin, the scientist who unearthed the first bone, told AFP on Thursday.
The dinosaur belongs to the sauropodomorph species, the same linage that would later include giant long-necked dinosaurs, said Griffin, a researcher at Yale University. Scientists believe it was an omnivore that ate plants, small animals and insects.
The skeleton was found during two expeditions in 2017 and 2019 by a team of researchers from Zimbabwe, Zambia, and the United States.
"I dug out the entire femur and I knew in that moment, that it was a dinosaur and I was holding Africa's oldest known dinosaur fossil," said Griffin, who at the time was a PhD candidate at Virginia Tech University.
His team's findings were first published in journal Nature on Wednesday.
Dinosaurs' remains from the same era had previously been found only in South America and India.
The palaeontologists selected the Zimbabwe site for digging after calculating that when all continents were connected in a single land mass known as Pangea, it laid roughly at the same latitude of earlier findings in modern day South America.
"The discovery of the Mbiresaurus is an exciting and special find for Zimbabwe and the entire palaeontological field," said museum curator Michel Zondo."The fact that the Mbiresaurus skeleton is almost complete, makes it a perfect reference material for further finds."
The dinosaur is named after the Mbire district, northeast of Zimbabwe, where the skeleton was found, and palaeontologist Michael Raath, who first reported fossils in this region.
"What this (discovery) does is it broadens the range that we knew the very first dinosaurs lived in," Griffin said.
Other specimens were discovered in the area, and all are held at the Natural History Museum of Zimbabwe, in Bulawayo.