The aim of this study was to assess the influence of cultivar and growth phase on the antioxidant activity (AOA) changes in common buckwheat (Fagopyrum esculentum Moench), as well as the its distribution in different plant parts. During 4 growth phases (GP) (buds formation - I, beginning of flowering - II, full flowering - III, full maturity - IV) stems, leaves, flowers, seeds were collected sequentially from 6 buckwheat cultivars - ‘Pyra’, ‘Spacinska’, ‘Kasho’, ‘Jana C1’, ‘Hrusowska’, ‘Emka’. The highest values of AOA were measured in flowers (GP III) in ‘Jana C1’ (93.17%) and the lowest value in stems (GP I) in ‘Spacinska’ (46.09%). The highest increase of AOA was observed in GP IV in stems in ‘Pyra’. Differences were compared for statistical significance at the level P < 0.05. Namen te raziskave je bil oceniti vpliv sorte in razvojnih faz navadne ajde (Fagopyrum esculentum Moench) na antioksidativno aktivnost različnih organov rastline. V štirih razvojnih fazah (GP; tvorba popkov-I, začetek cvetenja-II, polno cvetenje- III, polna zrelost-IV) smo vzorčili stebla, liste, cvetove in semena pri šestih sortah navadne ajde (‘Pyra’, ‘Spacinska’, ‘Kasho’, ‘Jana C1’, ‘Hrusowska’, ‘Emka’). Največja antioksidativna aktivnost (AOA) je bila izmerjena v cvetovih pri sorti ‘Jana C1’ (GP III, 93.17 %) in najmanjša v steblih pri sorti ‘Spacinska’ (GP I; 6.09%). Največje povečanje AOA je bilo izmerjeno v steblih pri sorti ‘Pyra’ v razvojni fazi GP IV. Statično ovrednotenje razlik je bilo opravljeno na ravni P < 0.05.