Investigators recovered the black-box flight recorders from the Nairobi-bound jet that went down early Sunday near Addis Ababa, the carrier Ethiopia Airlines said.
Flight ET302 crashed into a field just six minutes after takeoff as the pilot alerted controllers of "difficulties".
There were people from 35 countries on board, including some two dozen U.N. staff. Ethiopia decreed Monday a day of national mourning.
The aircraft was the same type of jet as the Indonesian Lion Air plane that crashed in October, killing 189 passengers and crew.
Airlines in Ethiopia, China, South Africa, Indonesia and the Cayman Islands said Monday they were suspending operations by their 737 MAX 8 fleets.
The move caused Boeing shares to tumble around 12 percent earlier in the day, before recovering about half its losses in mid-afternoon New York trading.
Jets grounded
Ethiopia Airlines said investigators had found the plane's flight data and cockpit voice recorders on Monday.
It said it had grounded its fleet of six remaining Boeing 737 MAX 8 planes pending analysis of the black box data.
"We assume we will find out the cause of the crash in the black box data," the airline said.
China also ordered domestic airlines to suspend commercial operation of the MAX 8.
There were eight Chinese nationals among the 149 passengers and eight crew on the Ethiopia flight.
Indonesia, which has 11 of the MAX 8 model planes, said it would "carry out inspections and temporarily prohibit Boeing 737 Max 8 from flying."
South Korea ordered an inspection of two MAX 8 planes flown by low-cost Eastar Jet.
Some other airlines said they were not cancelling MAX 8 flights, including Oman Air, flydubai, Turkish Airlines and Russia's S7.
Boeing has described the MAX series as its fastest-selling aeroplane ever, with more than 5,000 orders placed to date from about 100 customers.
State-owned Ethiopian Airlines, Africa's largest carrier, had ordered 30 MAX 8 jets in total, and China has received 76 from an order of 180.
The plane that crashed on Sunday was less than four months old. Ethiopian Airlines said it was delivered on November 15.
Plane on fire
The jet went down near the village of Tulu Fara, some 60 kilometers (40 miles) east of Addis Ababa.
"The plane was already on fire when it crashed to the ground. The crash caused a big explosion," one witness, Tegegn Dechasa, told AFP.
Another, farmer Sisay Gemechu, said the plane seemed to be aiming to land on an open field, but crashed before reaching it.
Inhabitants of the remote area looked on from behind a security cordon as inspectors searched the crash site and excavated it with a mechanical digger.
The single-aisle Boeing jet left a deep, black crater at the impact site.
Ethiopian Airlines said the pilot was given clearance to turn around after indicating problems shortly before the plane disappeared from radar.
The airline's chief executive Tewolde GebreMariam said the plane had flown in from Johannesburg early Sunday, spent three hours in Addis and was "despatched with no remark", meaning no problems were flagged, before leaving for Nairobi.
A committee comprising Ethiopian Airlines, aviation and transport authorities was set up to lead the crash investigation.
U.S. experts and Boeing will also take part.
The U.S. plane manufacturer cancelled the scheduled presentation Tuesday of its new long-haul jet, the 777X.
Author, student, aid workers
The crash cast a pall over a gathering of the U.N. Environment Programme, which opened in Nairobi on Monday.
At least 22 staff from several U.N. agencies were on the doomed flight.
Delegates hugged and comforted one another as they arrived at the meeting with the U.N. flag flying at half-mast.
Details of the passengers, including tourists, business travellers and humanitarian workers, have started to emerge.
Among them was Cedric Asiavugwa, a Kenyan third-year student at Georgetown University Law School in Washington.
He was heading for a visit home ahead of his graduation in the spring, the university said.
Kenya had the highest death toll among the nationalities on the flight with 32, according to Ethiopian Airlines.
Canada was next with 18 victims.
There were nine Ethiopians and eight each from Italy and the United States.
The airline said Britain and France each had seven people on board, Egypt six, and Germany five.
France, however, put its death toll at nine.
Britain also put its death toll at nine, including two dual nationals travelling on other passports.
Italian archaeologist Sebastiano Tusa, 66, died in the crash, his wife Valeria Patrizia Li Vigni was quoted as saying by the Corriere della Sera newspaper.
On Sunday, "the friends I met at mass said I shouldn't worry because bad news travels fast," she said.
"In the end it arrived anyway, and it destroyed my life. I felt the disaster coming... He hadn't even wanted to go."