A source with knowledge of the case told AFP the 76-year-old was found guilty of two charges related to illegally importing and owning walkie-talkies and one of breaking coronavirus rules.
The walkie-talkie charges stem from when soldiers raided her house on the day of the coup, allegedly discovering the contraband equipment.
Monday’s sentence adds to the penalties the court handed down in December when she was jailed for four years for incitement and breaching Covid-19 rules while campaigning.
Junta chief Min Aung Hlaing cut the sentence to two years and said she could serve her term under house arrest in the capital Naypyidaw.
December’s ruling drew international condemnation, and the Myanmar public reverted to old protesting tactics of banging pots and pans in a show of anger.
Ahead of the verdict, Manny Maung, a Human Rights Watch researcher, said further convictions would deepen nationwide discontent.
“The announcement of her last conviction resulted in one of the highest days of social media interactions from inside Myanmar, and deeply angered the public,” she told AFP.
“The military is calculating this (the cases) as a fear tactic but it only serves to direct more anger from the public.”
Journalists have been barred from attending hearings, and Suu Kyi’s lawyers have been muzzled from speaking to the media.
Under a previous junta regime, Suu Kyi spent long spells under house arrest in her family mansion in Yangon, Myanmar’s largest city.
Today, she is confined to an undisclosed location in the capital, with her link to the outside world limited to brief pre-trial meetings with her lawyers.
Besides Monday’s cases, she is also facing multiple counts of corruption—each of which is punishable by 15 years in jail—and of violating the official secrets act.
In November, she and 15 other officials, including Myanmar’s president Win Myint, were also charged with alleged electoral fraud during the 2020 elections.
Her National League for Democracy party had swept the polls in a landslide, trouncing a military-aligned party by a wider margin than the previous 2015 election.
Since the coup, many of her political allies have been arrested, with one chief minister sentenced to 75 years in jail, while others are in hiding.