Special court judge M Mazed Ali also imposed a fine of Rs 10 lakh on Bharali.
The case against her was registered by the state vigilance and anti-corruption branch in 2001 but the charge sheet was filed only this February.
Bharali owns posh residential apartments in Mumbai and Guwahati, two cars and has also investments in the share market.
She was in the news after claiming that the then chief minister Prafulla Mahanta had married her in a secret ceremony at a temple in Mumbai in March 2001. Mahanta had denied her claim.