IN VÉLEZ-SANTANDER, COLOMBIA.The effects of the extraction system (50% methanol or 50% methanol pH 2.0), volume/ material ratio, temperature, time and extractions with 70% acetone were evaluated in the total phenolic compounds (TPC) extraction and in antioxidant activities (AA) using FRAP and ABTS assays in guava fruit.The best yield was obtained when 0.5 g of guava were extracted first with 20 mL 50% methanol and then four times with 20 mL 70% acetone during 30 min at 50 °C.Among the different trials guava fruit exhibited high levels of AA as well as TPC.