It has been investigated, with the aid of routine cytochemical methods, whether any changes of the activity of oxydoreductases of G. candidum which has been intluenced by chemical factors affecting its growth, and with which it can contact in human organism or his environment, occur. The factors were: antibacterial antibiotic from tetracycline group /chlortetracycline/, antifungal antibiotic representing polyenes derivatives /nystatine/, heavy metal salt /mercuric chloride/, aniline dye /malachite green/. To evaluate cytochemical preparates in which the fungus ce lis have been classified according to intensity of enzymatic reaction the chi² test has been suggested. It has been proved that all the investigated compounds have significant changes in the fungus metabolism showing in the oxydoreductases activity deviations.