For seven days until June 18, the unique trial will take place in Stockholm District Court. A reserve day is scheduled for June 22.
Anna Lindstedt is suspected of acting on her own, and without a sign from the Ministry of Foreign Affairs, in the case of the imprisoned book publisher Gui Minhai by arranging a meeting last year.
It is the first time in more than 200 years that a Swedish diplomat is brought to justice, charged with crimes against the national security.
Through her defense attorney Conny Cedermark, Anna Lindstedt has denied the crime and welcomed an investigation.