In the dissertation entitled Optical Properties Of The Bark of Silken Dogwood, we studied the anatomical and biochemical characteristics, which influence the optical properties of the silken dogwood bark. Thereby, we also measured photochemical efficiency. Silken dogwood branches were gathered in the parking lot area of the Biotechnical Faculty of Ljubljana, in winter time. The research was carried out between the 11th and 15th January 2016, in the laboratory of the Biotechnical Faculty. We carried out the measurements of reflectivity and transmittance of the bark with a spectrometer. We used a fluorometer to measure the photochemical efficiency in light and darkness. Samples were also taken from the bark to measure individual parts under a microscope, with our interest mainly directed at 4 structures: cuticle, epidermis, bark and phloem. We used biochemical analysis to measure the quantity of chlorophylls and carotenoids, antocyanins, and UV absorbing substances. All measurements were carried out on ten different branches of silken dogwood. The results of our research have shown, that measured parameters explained low portion of the variability of the transmittance and reflectivity of the silken dogwood bark.