The richest 10 percent of Germans in 2007 owned around 61 percent of the country's privately held assets, up from 58 percent five years earlier, a report from Berlin economic institute DIW showed.
The poorest 70 percent owned just under nine percent of the country's wealth and 27 percent either own nothing or are in debt, according to the study.
Germans' total assets were valued at 6.6 trillion euros ($8.5 trillion), which amounts to an average 88,000 euros for each adult. That is a 10 percent increase over 2002, according to the poll commissioned by the Hans Boeckler Foundation, which is close to trade unions.
Total assets increased
But the median level, the midway point between the highest and the lowest, stayed stuck at 15,000 euros -- indicating that the rich got richer.
The wealth gap between what was once East and West Germany also widened, the study showed.
In the west, assets rose almost 11 percent between 2002 and 2007, but in the east they fell by just under 10 percent. Adjusted for inflation the fall was 17 percent.
"If politicians fail to act, poverty among the elderly in eastern Germany will grow sharply in the future," the report's authors Joachim Frick and Markus Grabka said in a statement.