Every foreigner working in Turkey needs a valid work permit. This permission is given by the Ministry of Labor and Social Security (MoLSS).
The vast majority of foreigners must simultaneously apply for a work visa in order to obtain a work permit. While you collect the documents required for the work visa and apply to the Turkish embassy or consulate in your country, your employer must submit the necessary documents to the Ministry of Labor and Social Security.
However, it is possible to apply for a work permit not only from your own country, but also within the borders of the Republic of Turkey. Foreigners are eligible to do so if they have obtained a residence permit with a validity of at least six months. Foreigners entering Turkey as tourists are not eligible for a work permit.