Ingeborg Rapaport passed the oral part of the exam last month with flying colours, and was awarded the degree on Tuesday at Hamburg University.
Ms Rapoport (then Syllm) finished her medical studies in 1937 and wrote her doctoral thesis on diphtheria - a serious problem in Germany at the time.
But because of Nazi oppression she has had to wait almost eight decades before being awarded her PhD.
Her mother was a Jewish pianist and under Adolf Hitler's anti-Semitic race laws, she was refused entry to the final oral exam.
She had written confirmation from Hamburg University that she would have received her doctorate "if the applicable laws did not prohibit Ms Syllm's admission to the doctoral exam due to her ancestry".
The university has now set right that wrong. Three professors from its medical faculty travelled last month to Ingeborg's sitting room in east Berlin to test her on the work she carried out in pre-war Germany.
They were impressed and a special ceremony took place at Hamburg University Medical Centre on Tuesday, in which she finally received the PhD that the Nazis stole from her.
"It was about the principle," she said. "I didn't want to defend my thesis for my own sake. After all, at the age of 102 all of this wasn't exactly easy for me. I did it for the victims [of the Nazis]."
To prepare for last month's exam, she enlisted friends to help her research online what developments there had been in the field of diphtheria over the last 80 years.
In 1938, as Germany became an increasingly dangerous place for Jews, Ingeborg fled to the US where she went back to university, finally to qualify as a doctor.
Within a few years she met her husband, the biochemist Samuel Mitja Rapoport, who was himself a Jewish refugee from Vienna.
But, in the 1950s, the McCarthy anti-communist trials meant that she and her husband were at risk because of their left-wing views, so they fled again, back to Germany.
This time she went to communist East Berlin, where she worked as a paediatrician, eventually becoming a paediatrics professor, holding Europe's first chair in neonatal medicine, at the renowned Charite hospital in East Berlin.
She was given a national prize for her work in dramatically reducing infant mortality in East Germany.