Thanks @Micha92 and @Thor.
Dear @mina,
Welcome to Wefugees.
To answer your question:
Theoretically it is possible to study accounting master program with mathematics bachelor degree, if someone has work experience as accountant or in financial field.
However, you should first search for the programs and then see what requirements are needed for. Each university or program has it's own criterias.
You should also pay attention to the fact that most of the english language master programms in this field have high tuition fee.
I recommend the DAAD website for the search:
https://***.daad.de/deutschland/studienangebote/studiengang/en/
On the left side you can search for specific programs (bachelor, master...) in specific language (english, german,...) and you can check which university has what.
If you are a refugee here in Germany, there are also university projects helping refugees to get integrated in the education system. For example HWT university (which has a master program for accounting).
We give educational counselling to refugees in Berlin in different languages (Farsi, Arabic, French...). So if you have more questions, you can contact us.
https://goo.gl/gQiu5R
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