Nowadays, a large number of aromatic and medicinal plants possess highly significant bioproperties, with numerous applications in medicine, pharmacy, cosmetology, and agriculture. This work aimed to conduct a phytochemical screening and assay of phytomarkers with biopharmaceutical potential and to assess the antioxidant and antibacterial activity of Persea americana Mill. kernel extracts in vitro. P. americana plant samples were collected in May 2017 in Kinshasa. Three standard strains were selected namely Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and Pseudomonas aeroginosa ATCC 9027 for microbiological assays. The phytomarker assay was used to detect total polyphenols, and the antibacterial activity was determined using the solid diffusion method on the Mueller Hinton medium to establish the minimal inhibitory concentration. Antioxidant activity was evaluated by the DPPH, ABTS, and Phosphomolybdate techniques. The findings showed that P. americana kernels contain secondary metabolites such as flavonoids, polyphenols, alkaloids, tannins, and triterpenoids, which may confer interesting biological activities. Quantitative phytomarker analysis of P. americana extracts showed a concentration of 69.70±3.07 mg/QE of total polyphenols and 27.53±1.15 mg/QE of flavonoids. All the extracts tested had low antibacterial activity against the three strains tested. However, the methanolic extract showed better antioxidant activity. In view of the IC50 values of our various fractions, it is clear that P. americana kernels possess interesting antioxidant properties.