She was 90 and is survived by the Union Minister and five daughters. Her husband had predeceased her.
Ghatowar, a former tea garden labourer of Dumordolong Tea Estate in Dibrugarh district, was suffering from various old age-related ailments including kidney failure.
The Union Minister, though not present during his mother's death, was currently in Dibrugarh in connection with campaigning for Panchayat polls scheduled on January 30.
Assam Chief Minister Tarun Gogoi along with BJP President Sarbananda Sonowal condoled her death.