Police said Sarma's mother, Mrinalini Devi, was on her way for morning walk at around 7 am when two miscreants in a bike stopped near her.
They snatched the gold chain which she was wearing in her neck. However, the lady did not sustain any injuries.
An FIR has been lodged in the Dispur police station and efforts are on to nab the culprits.
Sarma is considered to be one of the most powerful ministers in the 11-year-old Tarun Gogoi ministry and a potential succesor to the chief minister.