Anna Lindstedt is accused of going beyond her remit by holding unauthorised talks with a foreign power to gain the release of a Chinese-born Swedish citizen.
Gui Minhai, a Hong Kong bookseller, was later jailed by China for “illegally providing intelligence overseas”.
The prosecutor said Ms Lindstedt had put relations with China at risk.
In February 2019 Anna Lindstedt was recalled from China as ambassador after she was accused of brokering an unauthorised meeting at the Sheraton Hotel in Stockholm between Gui Minhai’s daughter, Angela Gui, and two Chinese businessmen said to have connections to the Chinese Communist Party.
Before the meeting Ms Gui had been campaigning for her father’s release, and then said she had been invited to the meeting by Ms Lindstedt, who told her “there were some businessmen she thought could help, and that they wanted to meet me in Stockholm”.