The World Health Organisation says more than half the annual estimated 150,000 deaths linked to climate change will come from the Asia-Pacific region.
The United Nations body says most of the fatalities will be the result of a greater incidence of diseases such as malaria, diarrhoea and malnutrition, as well as and flooding due to changing weather patterns.
The WHO director for the Western Pacific region, Shigeru Omi, says the impact of climate change will be felt more in developing countries, which have fewer resources to deal with it.
Mr Omi cited evidence that malaria was now appearing in areas such as the highlands of Papua New Guinea, which were once considered too cold for mosquitoes that spread the disease.
Global warming had also caused ocean levels to rise, already causing sea water to seep into ground water of Pacific island nations like Tuvalu and the Marshall Islands.
Mr Omi said climate change was causing seasonal changes to be more erratic, making it harder to predict planting seasons as well as flooding and droughts, leading to more deaths.
The WHO has allocated 10 million US dollars to study the effects of climate change on health and how to deal with it.