The airline is currently in talks with the U.S. planemaker over its fleet planes, a review brought on by the coronavirus pandemic, which has devastated the travel industry.
Asked if the airline could swap its orders to take fewer 777X jets and more Dreamliners, Sheikh Ahmed bin Saeed Al Maktoum told reporters: "It is always a possibility."
"We are assessing our fleet requirements as we speak."
Emirates, the world's biggest long-haul airline before the pandemic, has recently expressed frustration with Boeing over the 777X program, which is three years behind schedule, urging the planemaker to share more details on the in-production jet.
Sheikh Ahmed said the delays had been "tough" for Boeing, which is emerging from its worst crisis after fatal crashes of 737 MAX jets and a 20-month safety ban that has since been lifted.
Emirates reduced its order for 150 777X to 126 jets as part of a deal that saw the airline ordered 30 Dreamliners in 2019.
Sheikh Ahmed, who has headed Emirates since it was founded in 1985, did not say when the airline would decide on its future fleet.
The airline is due to report its annual results for the financial year ended March 31. Sheikh Ahmed said it had been a very tough year, with the airline carrying around 30% of the 56.2 million passengers it carried in the previous year, without providing further details.
He said he was optimistic for the upcoming summer travel season, even as the airline was reviewing its cash reserves on a monthly basis due to the deterioration in demand caused by the pandemic.
However, Sheikh Ahmed suggested the airline was taking a conservative approach to restore capacity, telling reporters Emirates would only operate flights that make commercial sense.
"We don't just open a route for the sake of opening or just for a publicity reason."
