The man's name was not made public by prosecutors, in accordance with German privacy laws.
The public prosecutor in the western city of Giessen, near Frankfurt, said in a statement that the man worked at the Sachsenhausen concentration camp between 1943 and 1945.
The man, who was a minor at the time of the alleged crimes, is accused of "having assisted in the cruel and insidious killing of thousands of prisoners," prosecutors said.
The man will face a juvenile court because he was under the age of 18 when he served at Sachsenhausen.
The statement added that the trial is expected to be in Hanau, close to the man's home, in accordance with juvenile law.
A psychiatric assessment of the suspect in October 2022 found that he is fit to stand trial within certain limits, the statement concluded.
Germany is racing against time to bring the last surviving perpetrators of Nazi war crimes – now well into old age – to justice.
Last year, another former Sachsenhausen guard, aged 101, was sentenced to five years in prison after being convicted for aiding and abetting the murder of 3518 people during the Holocaust.
A 96-year-old German woman fled before standing trial for crimes she was alleged to have committed while working as a stenographer and typist in the commandant's office at the concentration camp in Stutthof, near what is now the Polish city of Gdansk.
She was later found by local authorities and brought before court, where she was convicted on similar charges.
Sachsenhausen was built by prisoners and opened in 1936.
Of the roughly 200,000 prisoners who passed through the camp, around 100,000 are thought to have died there.
During World War II, the camp's inmate population fluctuated between about 11,000 and 48,000 people.
An estimated 6 million Jews were killed in Nazi concentration camps during World War II.
Also killed were hundreds of thousands of Roma people, political opponents, homosexuals, and people with physical or learning disabilities.