The effect of processing on potential changes of antioxidant activity (DPPH and ABTS), total phenolic content (TPC) and total flavonoids (FLAV) of feijoa pulp during storage was investigated. In addition, possible modifications in the phenolic composition of the pulp. The pulp was subjected to refrigeration (control, 5 °C), pasteurization (85 °C/5 min) and irradiation (2.0 kGy). TPC, FLAV, DPPH and ABTS were measured during 28 days, whereas the identification and quantification of phenolic compounds were conducted after processing. The results were submitted to principal component analysis (SAS 9.4). Pasteurization preserved TPC, DPPH and ABTS for 21 days, while in the irradiated samples and control, the values were decreased and FLAV were maintained at high levels. The profile of phenolic compounds was different for each sample with six compounds being identified.