Calcium is the most abundant mineral in human body. 99% of calcium in body is found in bones and teeth while the rest 1% is found in blood and soft tissue. That 1% plays an important role in biological processes and it's concentration is strongly regulated in cells with parathyroid hormone and calcitriol. In cells, it is found in greater concentrations in mitochondrium and endoplasmatic reticulum which serves as intracellular storage for its regulation. Extracellular calcium serves as a regulator of potential difference in cell membranes. Nerolidol is sesquiterpene alcohol naturaly occuring in many esential oils of different plants with floral odor. Becouse of its presence in human everyday life, scientists became interested in examination of its biological properties. Different effects of nerolidol on tumorigenic cells have been examined and they gave interesting results encourageing further researches. It is interesting to examine the effect of nerolidol on the amount of intracellular calcium in different types of human cancer cells. Disorders in calcium regulation triggers cascade of cellular events that lead to apoptosis, induced programed cell death which is the goal of every anticancer therapy. With positive cell response in the change of the amount of intracellular calcium in this experiment it opens the doors to furher researches in nerolidol effects on healthy and tumorigenic cells. Datas were collected filming fluorescence of chelate of calcium and fluorescentic reagent Fluo-3 with flow cytometer Accuri C6 in human bladder carcinoma cells (TCCSUP) while being treated with different concentrations of nerolidol.