Lakhan Rajvanshi, a resident of Nalanda district's Pandiptpur area, critically injured in the Patna serial blasts, died Thursday, a police officer said.
After initial treatment in Patna, Rajvanshi had returned to his village and was being treated at a local hospital, the family members said.
At least six people were killed and nearly 100 injured in the serial blasts in Patna ahead of a rally addressed by the Bharatiya Janata Party's prime ministerial candidate Narendra Modi.
Besides, a suspected bomber was also killed.
The NIA has arrested four people including Mohammed Imtiyaz Ansari in connection with serial blasts in Patna.
The NIA is probing into the serial blasts.