Dagmawit Moges said the investigators had restored all relevant data from the black boxes.
Moges provided no additional details on the alleged "similarities" between the two crashes, but said they were "under further investigation."
Ethiopian Airlines Flight 302 crashed on March 10, six minutes after launch, killing all 157 people on board. It was the second disaster involving a new Boeing 737 Max 8 in less than six months.
In October, all 189 people were killed aboard Lion Air Flight 610 when the plane fell over the Java Sea in Indonesia 13 minutes after launch.
Investigators suspect that the Lion Air crash may have been caused by a pitch sensor outside the aircraft transmitting incorrect data, possibly resulting in automated flight software called Maneuvering Maneuvering (MCU) Augmentation System, the system forced aircraft nose down.
According to a preliminary report of the crash, the pilots manually corrected an "aircraft nose down" two minutes after takeoff and performed the same procedure over and over again before the plane ran its nose into the Java Sea, the report said ,
On Sunday after Moges & # 39; commented Boeing Chairman, CEO and CEO Dennis Muilenburg, explaining that the company "continues to support the investigation and work with the authorities to evaluate new information as it becomes available."
Muilenburg added that the company "is completing the development of a previously announced software update that addresses the behavior of the MCAS Flight Control Act in response to erroneous sensor inputs."
Ethiopian Airlines CEO Tewolde GebreMariam said the Flight 302 pilot had "flight control issues" just before the plane crashed.
"He had difficulty with the aircraft's flight control, so he asked to return to base," GebreMariam said. The pilot got permission when the flight from the radar disappeared.
CNN's Anna Cardovillis reported from Addis Ababa that Dakin Andone reported and wrote this story from Atlanta. CNN's Thom Patterson contributed to this report.