Evaluation of Financial Stability of Azerbaijan Commercial Banks Using the Fuzzy Logic Methods Ramin Rzayev 1,2 , Sevinj Babayeva 1 , Tofik Babayev 1 , Hafiz Bayramov 3 1 Institute of Control Systems of ANAS, B. Vahabzadeh str. 9, AZ1141 Baku, Azerbaijan 2 Azerbaijan State Oil and Industry University, Azadlig ave. 34, AZ1010 Baku, Azerbaijan 3 Azerbaijan State University of Economics, Istiqlaliyyat str. 6, AZ 1000 Baku, Azerbaijan babayevasevinj@yahoo.com Abstract. The paper considers two fuzzy methods of multifactor assessment of alternatives and groups of financial indicators, which are used to assess the fi- nancial stability of the four leading commercial banks of Azerbaijan. At the same time, the choice of financial ratios that have the greatest impact on the financial stability of a bank is dictated by the desire to establish a strict correlation between the financial condition of banks and these factors. Therefore, not trying to invent new ratios to assess liquidity, profitability, capital adequacy, quality of assets and liabilities, the paper employs a set of ratios that are most commonly used in var- ious methods for selected financial indicators of bank stability. Keywords: Financial Stability of Bank, Financial Ratio, Fuzzy Set. 1 Introduction Analysis of the activities of a commercial bank (CB) is a system of special knowledge related to the study of the financial and economic results of its activities, identifying factors that have a significant impact on its financial stability, identifying trends and justifying development directions. In [1, 2], we proposed a method for evaluating the financial indicators of CB for the current period of their financial activities, based on the use of fuzzy methods of multifactor assessment of alternatives. At the same time, the method itself was tested on the example of hypothetical CB, which in itself is not quite convincing from the point of view of practical significance. Therefore, without going into details of the essence of the problem, which we described in [1], we will proceed directly to the statement of the problem of evaluating the financial sustainabil- ity of CB, using the examples of current financial statements of the leading commercial banks of Azerbaijan. 2 Problem Statement We selected four successful banks of Azerbaijan as the evaluated alternatives: a1 – “Yapi Kredi Bank” CJSC; a2 – “Capital Bank” OJSC; a3 – “Express bank” OJSC; a4 –