He was 85. He is survived by four daughters.
He breathed his last at about 9:30 am at the city's Combined Medical Institute (CMI).
Official sources said Swami, who became the first CM of the North Indian state when it was created out of Uttar Pradesh in 2000, will be cremated with state honours at 4 pm at Lakhibagh in the city.
His mortal remains have been kept at his ancestral home here for people to pay their last respects. The funeral procession will start at 2 pm, family sources said.
Proceedings in the state Assembly were adjourned for the day after paying condolences to Swami.
Describing his death as a personal loss, Chief Minister Vijay Bahuguna said Swami was an inspiring leader to whom he often went to seek guidance.
Leader of Opposition in the state Assembly Ajay Bhatt said as chief minister of Uttarakhand, Swami gave total freedom to his ministers to work in the interest of people.
Swami represented Dehradun seat in Uttar Pradesh Assembly and was also a member of the neighbouring state's Legislative Council in 1984, 1990 and 1996.
Born at Narnaul in Haryana on December 27, 1927, Swami was a lawyer and social worker before joining politics.
His political career began when he won from Dehradun seat for the first time as a candidate of erstwhile Jana Sangha.
He was also elected to Uttar Pradesh Legislative Council from Kumaon and Garhwal graduate constituencies in 1984, 1990 and 1996.
Swami, who was made vice chairman of Uttar Pradesh Legislative Council in 1991, rose to become its chairman in 1992 and remained at the post till 2000.
When Uttarakhand was created out of Uttar Pradesh on November 9, 2000, he became its first Chief Minister and remained at the helm till October 29, 2001.
Expressing their grief at the death of Swami, legislators from across the political spectrum remembered him as a warm- hearted person who was always available for young members to guide them.
Dehradun: The first Chief Minister of Uttarakhand Nityanand Swami died here Wednesday morning following prolonged illness.
First Published: Wednesday, December 12, 2012, 15:22