The electrical properties of the supported lipid bilayer membrane (s-BLM) of egg phosphatidylcholine (PC) selfassembled on agar surface were examined. To characterize the insulating properties of s-BLMs, electrochemical impedance spectroscopy (EIS) was used. The analysis of impedance spectra in terms of an equivalent circuit of agar/electrolyte and agar/s-BLM/electrolyte in the frequency range of 0.1 Hz-10 kHz was performed. The high-density lipoproteins (HDL)/s-BLM interaction in the concentration range from 20 μg/ml to 80 μg/ml of HDL was investigated. It is evident that treatment of s-BLM with HDL resulted in an increase of the lipid film resistance and a decrease of membrane capacitance., M. Legiň, G. Laputková, J. Sabo, L. Vojčíková., and Obsahuje bibliografii