Nandini from Doddihalli in Belur taluk gave birth to the baby on May 23 around 6.15 pm at Hassan Institute of Medical Sciences.
"The baby was delivered after conducting a caesarean surgery" HIMS Medical Superintendent Dr K Shankar told PTI.
"It is the heaviest baby so far reported in India, last one reported was somewhere around 5.8 kgs," he said.
Nandini's husband Arun works for a bakery.
Both baby and mother are healthy, but as the case is "unusual" doctors have decided to keep the baby under observation and are assessing the reason for the over weight.