Satayaprakash Sharma, aged 58, facing trial in a murder case, died in Maharao Bheem Singh hospital yesterday, Jailor, Kota Central Jail, Narendra Swami said.
Sharma, lodged in the Kota prison for the past seven years, was suffering from diabetes and also had blood pressure problem.
He was taken to the hospital for medical check-up on Friday and again on Saturday when his condition deteriorated, the Jailor said.
The undertrial died during treatment in the hospital, he said.
Sharma was arrested in December 2007 in a murder case of a property dealer who was stabbed and shot dead in front of Chambal Garden in October 2006.
The trial is in the final stage in the court, the Jailor said.