The Boeing 737 MAX 8 is the same type of plane as the Indonesian Lion Air jet that crashed soon after takeoff from Jakarta in 2018 - killing 189 people.
The plane was a Boeing 737-800 MAX, the airline said.
A statement by the airline earlier on Sunday said a search and rescue operation was underway.
The aircraft's manufacturer, Boeing, stated: "Boeing is aware of reports of an airplane accident and is closely monitoring the situation".
The plane is the latest version of the 737, the world's best selling modern passenger aircraft and one of the industry's most reliable. "The villagers said that it was a plane crash, and we rushed to the site".
The Lion Air cockpit data recorder showed that the jet's airspeed indicator had malfunctioned on its last four flights, though the airline initially said problems had been fixed.
Flight ET 302 crashed near the town of Bishoftu, 62 kilometres southeast of the capital Addis Ababa, the airline said, adding that the plane was a Boeing 737 MAX8. It was on a regularly scheduled flight from Addis Ababa to Nairobi, Kenya.
Sunday's crash, however, had "no fluctuations and all of the sudden transmission" ceased, he said. They included 32 Kenyans and nine Ethiopians. CS James Macharia said a team led by Principal Secretary Esther Koimett has been sent to Ethiopia.
A statement from Ethiopian Airlines indicates the flight had 149 passengers on board as well as eight crew members.
The crash shattered more than two years of relative calm in Africa, where travel had always been chaotic. The carrier had been using five of the planes and awaiting delivery of 25 more.
The jet's last maintenance was on February 4, and it had flown just 1,200 hours.
New Prime Minister Abiy Ahmed has been promising to open up the state-owned airline to domestic and global investors.
"We are saddened by the news of an Ethiopian Airlines passenger aircraft that is reported to have crashed 6 minutes after takeoff en route to Kenya". The flight has crashed 60km south-east of the airport.