During the vegetative propagation of willow Salix babylonica, stem cuttings develop adventitious roots that accumulate high levels of anthocyanins in the presence of light. This phenomenon has been known earlier, but there are no data in the available literature regarding the profile of these pigments. The aim of the study that has been carried out was to determine the composition and content of anthocyanins and accompanying other phenolic compounds and salicinoids in adventitious roots of S. babylonica. Identification and analysis of anthocyanins were carried out using micro-HPLC-MS/MS-TOF, while HPLC-MS/MS was used to analyze phenolic acids, flavonoids and salicinoids. In addition to these analyses, histological observations were made using a microscope. On microscopic cross-section, a red color was found only locally – in some sub-epidermal cells of the exodermis and parenchyma cells of the cortex. In S. babylonica roots, eleven glycosides of cyanidin, delphinidin, petunidin, peonidin, pelargonidin and malvidin have been demonstrated. Quantitatively, in roots developed in darkness main anthocyanin was delphinidin glycoside while in the in light exposed roots main anthocyanin was cyanidin glucoside. The increase in anthocyanin content in roots exposed to light for three weeks was several hundred times that of those kept in the dark, and their total level was more than a hundred times higher than that of flavonoids, phenolic acids and/or salicinoids. This likely means that anthocyanins are major participants of the protection system in response to stress caused by exposure of S. babylonica roots to light.