Ngar Min Swe was sentenced for sedition on Tuesday, Yangon's Western District Court spokesman Htay Aung told AFP.
"He was convicted... for writing abusive posts on Facebook against State Counsellor Aung San Suu Kyi, making people get the wrong impression of her," Htay Aung said.
Myanmar faces widespread condemnation for infringing on freedom of expression following the jailing earlier this month of two Reuters journalists who reported on the Rohingya crisis.
Ngar Min Swe worked as a columnist under the previous military-backed government. He has spent the years since Suu Kyi's National League for Democracy party rose to power in 2016 penning screeds against her and the party.
He was arrested on July 12, the same day he posted about Suu Kyi receiving a kiss on the cheek from US President Barack Obama during his state visit in 2013.
This innocuous gesture of greeting came in for criticism from a conservative Myanmar public, especially supporters of the army-aligned Union Solidarity and Development Party -- like Ngar Min Swe, who took to social media to make sexist inferences about the state counsellor.