The 63-year-old woman died on the way to hospital on the island of Aitutaki, Prime Minister Mark Brown said in a statement.
"It is with great sadness that I announce that we have recorded our first in-country death attributed to Covid-19," Brown said.
"The deceased was a 63-year-old woman on the island of Aitutaki.
"She had had all three anti-Covid vaccinations, but also had several serious underlying health conditions."
"It is tragic, but not unexpected that we might lose someone to Covid.