The influence of extrusion parameters on changes in phenolics amount and composition as well as antioxidant activity of bean (Phaseolus vulgaris L.) was presented. Total phenolics in varieties varied from 777 to 996 mg/100g d.b. Myricetin, quercetin, kaempferol, cyanidin, chlorogenic acid, caffeic acid, ferulic acid and p-coumaric acid were identified. Content of total phenolics decreased during extrusion about 30–32%. Also, content of the majority of phenolic compounds was lowered after extrusion in comparison to raw seeds. The lowest losses of phenolics was observed in extrudates obtained of processing parameters: 20% initial humidity, temperature 120°C. Antioxidant activity, evaluated in β-carotene/linoleic acid model system, both raw seeds and extrudates were similar in two investigated varieties. The highest decrease of antioxidant activity was observed in extrudates obtained with parameters 20% humidity and temperature 180°C.