The article discusses quantitative methods of assessing systemic risk of the financial sector and the possibilities of their practical application. Systemic risk, which is manifested in the failure of financial services provision and deterioration of the financial system, is a complex concept that can be realized in several forms: the risk of infection, exogenous shock, leading to a simultaneous decline in all financial institutions, and the risk of «financial fragility accumulation". The main causes of the imbalances in the system are unjustified loose standards of risk assessment during economic booms, procyclical behavior of economic agents and asymmetric information. The spread of the risk is associated with the financial accelerator me...