FIELD : biotechnology.SUBSTANCE : invention refers to medicine and biotechnology, particularly to determination of estrogen and progesterone expression by HER-negative breast cancer cells. Method involves preparation of paraffin blocks from tumor tissue and histological sections, their dewaxing in hexane. Then, non-dyed dewaxed histological sections of tumor tissue are subjected to fluorimetric analysis, fluorescence excitation spectra are measured from 230 to 360 nm at detection wavelength 410 nm, and ratio between intensities of curves with maxima within 262 and 303 nm is determined (I262/I303) and presence of maximum at 340 nm; at I262/I303 less than 1.0 and absence of peak on spectrum of fluorescence excitation at 340 nm conclude presence of receptors to estrogen and progesterone; at I262/I303, greater than and equal to 1.0, and the presence of a peak on the fluorescence excitation spectrum at 340 nm, the absence of estrogen and progesterone receptors is stated.EFFECT : invention increases objectivity of obtained results.1 cl, 3 dwg, 2 ex