During the expedition that lasted more than a month, scientists drilled the ice cores at a mountain pass near the East Rongbuk glacier, which covers the north collar of the Mount Everest, Xinhua reported.
The longest ice core measures 142 metres. It is the longest ever obtained from the mountain, said Kang Shichang, a research fellow at the Qinghai-Tibetan Plateau Institute under the Chinese Academy of Sciences.
The ice cores will be used to study climate and environmental change, he said.
The expedition also found a recent escalation in the melting of the East Rongbuk glacier, with some ice towers on the edge of the glacier disappearing and some new ice crevasses developing further in comparison to what scientists saw in the region in the 1990s, Kang said.
"This indicates that climate and environmental changes have had an obvious impact on Mount Everest," Kang said.
The study could take one to two years, during which researchers will analyse stable isotopes and organic pollutants in the ice cores.
Some samples will be sent abroad for further study.