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The purpose of this work was to determine the content of several constituents of the unsaponifiable fraction of 13 olive oil samples from various regions of Algeria, while assessing their antioxidant and antibacterial activities against 8 potentially pathogenic ATCC strains. The total polyphenol content in the samples varied significantly (p < 0.05) from one extract to another. The most significant values were recorded for the extracts from Skikda and Tissemsilt (207.97 ± 1.75 mg gallic acid/kg and 202.97 ± 2.67 mg gallic acid/kg, respectively). The total flavonoid content in the various extracts was variable. The highest levels were recorded in the extracts from Aïn Defla and Blida. While the extract from Jijel was the richest in flavonols, with a value of 258.22 ± 13.00 mg/kg, no correlation was found between total polyphenols and total flavonoids. The behavior of bacterial strains varied between sensitivity, extreme sensitivity, and resistance to the phenolic extracts, with a negative correlation between total polyphenol content and antibacterial activity. The lowest MICs were recorded for the extracts that showed the largest inhibition zones diameters.