The passenger, N K Kumar, who is in his 40s, has been hospitalised at a hospital in Nagpur.
"The passenger is in ICU and is stable. We wanted to move him to Delhi for better medical care but doctors have advised us against it," according to Air India spokesperson Dhananjay Kumar.
Delhi-Bangalore AI flight 803, with 158 passengers onboard, took off from Indira Gandhi International Airport here at 6.09 am and was diverted to Nagpur at 7.50 am.
The plane landed at Bangalore's Kempegowda International Airport at 9.25 am after a delay of 30 minutes.