An important scientific interest has been given to the potential healthpromoting properties of flavonoids due to their discovered wide range of activities in the prevention of common diseases, including coronary heart disease, cancer and other disorders. These effects came out to be related to the various biological or pharmacological activities of flavonoids, including antimicrobial, immunomodulatory or antithrombotic activities. Plants of the Taraxacum genus are being used as an herbal remedy to prevent, manage, and even ameliorate such human disorders due to its wide range of phytochemicals. The present paper emphasises the comparative content of flavonoids from vegetal organs of Taraxacum officinale F.H. Wigg (dandelion), perennial plant collected from different regions of Romania and evaluates the antioxidant potential of dandelion hydroalcoholic extracts. Mature vegetal product was collected in May 2022, from the eastern area of Transylvania, southern area of Dobrogea and Central Plateau of Moldova. The fresh plant was dried, ground to a fine powder and extracted 10% concentration, in 50:50 (v:v) ethanol and 70:30 (v:v) ethanol, using the conventional method of cold maceration. The obtained hydroalcoholic extracts were analysed by UV-Vis spectrophotometry. Total flavonoids concentration was highest in ethanol extracts of the plants collected from the Moldova region for all analysed vegetal organs - Radix, Herba, Flower and Mix. The influence of climate and soil on Taraxacum officinale plants from Dobrogea, Moldova and Transylvania areas determined significantly different values of the concentration of bioactive principle analysed and supports us to continuate the studies on the content of bioactive principles and the therapeutic activity of this valuable vegetal product from the Romanian spontaneous flora.