The convicts, including an active pro-democracy activist, had been charged with "brutal and inhumane acts of terror", according to the Global New Light of Myanmar.
According to the official journal, the executions followed "prison procedures", without specifying how or when they were carried out.
Since the military coup of February 1, 2021, Burma has sentenced dozens of opponents of the junta to the death penalty.
Phyo Zeya Thaw, a former lawmaker from Aung San Suu Kyi's National League for Democracy party, was arrested in November and sentenced to death in January for violating the anti-terrorism law.
The other two prisoners executed are two men accused of killing a woman they suspected of being a junta informant.
The ruling army continues a bloody repression against its opponents with more than 2,000 civilians killed and more than 15,000 arrested since the coup, according to a local NGO.
She also faces genocide charges against the Rohinngya. In 2017, more than 740,000 members of this Muslim minority found refuge in makeshift camps in Bangladesh to escape the abuses of the military.
