96-year-old Iyengar had been ailing since some time and was admitted to a private hospital here a week back. He was put on dialysis after his condition worsened two days back.
He breathed his last at 3.15 AM.
Iyengar, honoured with Padma Vibhushan, is survived by a son and daughter.
The legendary yoga guru was admitted to a city hospital on August 12 following complaints of acute breathlessness and palpitation, Dr Deepali Mande, who attended on him, told PTI.
"He did not want to be admitted to hospital even though he was unwell at home for almost three weeks. Iyengar had a cardiac (ailment) history. His condition subsequently worsened leading to renal failure after which he was put on dialysis," she said.
During the last phase, Iyengar was feeling drowsy, she said.
"He was not keen on having any food," the doctor added.
Iyengar was considered one of the foremost yoga teachers in the world and had written many books on yoga practice and philosophy including 'Light on Yoga', 'Light on Pranayama', and 'Light on the Yoga Sutras of Patanjali'.