Informal employment is seen as an important problem in developing countries. Although unregistered employment contributes to the country's economy in terms of production, it can negatively affect macroeconomic indicators such as tax loss and unemployment. Unregistered employment can be made up of nationals of the countries themselves, as well as foreign workers. The aim of this study is to reveal in which sectors Syrian refugees are preferred in unregistered employment in Turkey. Fuzzy TOPSIS was used as a method in the study. Fuzzy TOPSIS gives a ranking according to alternatives and criteria. Analysis results show that Syrian refugees are preferred in agriculture, construction and textile sectors, respectively, in unregistered employment in Turkey. With these results, it is suggested that Turkey's go-to legal regulations in immigration policies and unregistered employment and those asylum seekers should be evaluated at the legal level regarding the country's economy.