The report found that women in full-time jobs earn an average of 21.6 percent less than their male colleagues. This is significantly more than the average gender wage gap of the 34 industrialized countries that make up the OECD, which is 16 percent.
Of OECD countries, only Japan and Korea have a bigger average wage gap.
Germany's gap is even bigger in the public sector, where women earn 23 percent less than men.
The OECD expressly criticised the lack of women in management positions in Germany. “When it comes to women in leading positions, Germany is lagging a long way behind in international comparison,” the survey said.
According to the stats, only three percent of German management board seats are occupied by women, the lowest figure in Europe, and well behind Japan, Mexico, the US, and Russia.
The OECD average is 10 percent, while countries closer to Germany, like France, Sweden, Finland and Slovakia all have between 15 and 20 percent on management boards.
Many countries, including Spain, Iceland, France, Belgium and the Netherlands, are considering imposing gender quotas on management boards, and the European Commission is also putting pressure on leading European companies to improve its gender quota. Germany has so far declined to take this step, despite the damning figures.
The OECD identified Germany's underdeveloped childcare infrastructure as one of the key reasons for the poor results. The lack of kindergarten and day-care places is hindering many women from getting back into work, the organisation said. Only 18 percent of German children under the age of two have access to day-care – around half the OECD average.