A total 3,498 people from crisis-hit Greece took German citizenship last year, a 25 percent drop compared to 2012, official data showed.
Overall some 110,000 foreigners became nationals of Europe's biggest economy in 2013. The largest number came from Turkey, at 27,970, despite a 16 percent drop compared to 2012, followed by people from Poland, Ukraine and Greece.
The number of Greeks who assumed German citizenship in 2012 was 4,167.
To apply for German citizenship, foreigners generally have to live in the country for at least eight years and speak the language.