A Bangladeshi and a Korean national died while descending from the summit of Mount Everest on Monday night, a Nepali newspaper reported quoting officials.
The climbers have been identified as Mohammad Khalid Hussain, 35, of Bangladesh and Sung Ho-Seo, 34, of Korea, according to The Kathmandu Post report.
Khil Lal Gautam, an official at tourism ministry, told Post that Hussain lost his life at 8,600 metres.
Ho-Seo, who had climbed the peak without supplemental oxygen, refused to put on oxygen mask on returning to tent as suggested by Sherpa guides.
Ho-Seo argued that he would manage without oxygen since he had climbed the Everest without it.
He, however, died at 8,000 metres South Col inside his tent.
According to an AFP report, Hussain died in his tent a few hours after successfully climbing the summit.
"The exact cause of death is unknown, but altitude played a part," Gyanendra Shrestha, a tourism minister official told AFP, adding that the bodies would not be recovered until after the summit season ended so as not to interrupt other climbers.
Both men perished in the "death zone" -- above 8,000 metres, notorious for its difficult terrain and thin air.
Five other climbers have died on the 8,848-metre (29,029-foot) mountain this season.
Early in the season Mingmar Sherpa, 47, a member of an elite team known as the "icefall doctors" who set up climbing routes, plunged to his death.
DaRita Sherpa, 47, died from what is believed to have been cardiac arrest earlier this month. Commercial guide Lobsang Sherpa, 22, also plunged to his death. A 50-year-old Russian climber, Alex Bolotov, was found dead near the famed Khumbu Icefall crevasse on May 15.
Namgyal Sherpa, who had led expeditions to clear garbage and bodies from Everest, died May 16 while descending from his tenth successful summit.
Some 300 people have perished trying to reach the summit during the last six decades. The bodies of some of them remain on the mountain.
May is considered the best time for climbing in the Nepalese Himalayas because of mild weather and some 300 people have reached the top of Everest so far this year.
But a brawl that erupted last month between three European climbers and Nepalese guides on the mountain cast a shadow over this year's season, which marks the 60th anniversary of the maiden ascent by Tenzing Norgay and Edmund Hillary.