Australian journalist Cheng Lei – who was imprisoned in China on similarly opaque espionage charges – was freed last month after three years in detention.
Cheng’s return followed sustained lobbying from the Australian government, raising hopes that Yang might also soon be released.
Yang’s sons said they hoped Albanese “can achieve a second miracle by saving our father”.
“Like Cheng Lei, our father cherishes the freedoms and protections that come with his Australian identity.”
His sons also described the “particularly cruel” treatment they believe their father is facing, deprived of his beloved books in a cramped room where he is forced to “eat, drink, defecate and urinate”.
“At most, some rays of sunlight occasionally come through one or two panes of glass and flicker fitfully,” Yang told his sons.
Yang, who denies the spying claims, was arrested on a rare trip back to China in January 2019.
The writer and academic – who also goes by the pen name Yang Hengjun – has previously told supporters he was tortured at a secret detention site and fears forced confessions may be used against him.
His closed-door trial was heard in Beijing in mid-2021, with Yang still awaiting the verdict.
Attempts to raise Yang’s situation have irked Chinese officials in the past, who have told Australia to stop meddling in the country’s justice system.